What Are Hydrophytes: Information About Hydrophyte Habitats


By: Mary H. Dyer, Credentialed Garden Writer

What are hydrophytes? In general terms, hydrophytes (hydrophytic plants) are plants that are adapted to survive in oxygen-challenged aquatic environments.

Hydrophyte Facts: Wetland Plant Info

Hydrophytic plants have several adaptations that allow them to survive in water. For example, water lilies and lotus are anchored in the soil by shallow roots. The plants are equipped with long, hollow stems that reach the surface of the water, and large, flat, waxy leaves that allow the top of the plant to float. The plants grow in water as deep as 6 feet.

Other types of hydrophytic plants, such as duckweed or coontail, are not rooted in the soil; they float freely on the surface of the water. The plants have air sacs or large spaces between the cells, which provide buoyancy that allows the plant to float on top of the water.

Some types, including eelgrass or hydrilla, are completely submerged in water. These plants are rooted in the mud.

Hydrophyte Habitats

Hydrophytic plants grow in water or in soil that is consistently wet. Examples of hydrophyte habitats include fresh or salt water marshes, savannahs, bays, swamps, ponds, lakes, bogs, fens, quiet streams, tidal flats and estuaries.

Hydrophytic Plants

Hydrophytic plant growth and location depends on a number of factors, including climate, water depth, salt content, and soil chemistry.

Plants that grow in salt marshes or along sandy beaches include:

  • Seaside plantain
  • Sea rocket
  • Salt marsh sand spurrey
  • Seaside arrowgrass
  • High tide bush
  • Salt marsh aster
  • Sea milwort

Plants that commonly grow in ponds or lakes, or in marshes, swamps or other areas that are flooded by at least 12 inches of water for most of the year include:

  • Cattails
  • Reeds
  • Wild rice
  • Pickerelweed
  • Wild celery
  • Pond weeds
  • Buttonbush
  • Swamp birch
  • Sedge

Several interesting carnivorous plants are hydrophytic, including sundew and northern pitcher plant. Orchids that grow in hydrophytic environments include white-fringed orchid, purple-fringed orchid, green wood orchid and rose pogonia.

This article was last updated on

Read more about General Water Plant Care


Vegetation Identification for Wetland Delineation: North

This course is eligible for continuing education credits toward the Society of Wetland Scientists’
Professional Wetland Scientist (PWS) Certificate Program.

In accordance with Rutgers University's social distancing policy related to COVID-19, this class has been rescheduled for May 2021 with an online format. Learn more and register for the upcoming offering!

May 19-20, 2020
8:30am - 5:00pm (Check-in time on Day 1: 8:00am)

Wetland plants, also known as hydrophytes or hydrophytic vegetation, have adaptations that enable them to grow and reproduce with their roots in water or saturated soil for at least part of the year. In contrast, plants that cannot survive in saturated conditions are commonly referred to as upland plants.

Along with hydric soils and hydrology, the presence of wetland plants is one of the primary factors involved in the identification of wetland areas and the delineation of wetland boundaries. Therefore, the ability to identify wetland plants and distinguish between upland and wetland plant species is an essential step in the wetland delineation process.

In this two-day course, you will learn how to identify plant species frequently encountered by wetland delineators in northern and central New Jersey and neighboring New York and Pennsylvania. By the end of the course, you will be able to use two common field guides to quickly and confidently identify wetland plant species that are important in determining if an area meets the hydrophytic vegetation criterion for wetland delineation.

Students can expect to see over 100 different plant species, including trees, shrubs, and herbaceous plants, while learning how to use two basic field guides for identifying wetland and upland plants. Guided by instructor and wetlands expert Ralph Tiner, students will have the opportunity to explore vegetation in freshwater wetland habitats typical of the region.

This is a field-based course, so please dress accordingly for the outdoors!

NOTE: If you are planning to achieve the Wetland Delineation Certificate, we require that you complete this course prior to attending the Methodology for Delineating Wetlands course.

Click on the tabs below for more details about this wetland vegetation identification course.

Featured Topics Covered in this Vegetation Identification Course:

  • Introduction to Plant Identification and Wetland Plant Indicator Statuses
  • Use of Plant Identification Keys in the Field
  • Plant Names, Plant Groups, General Plant Morphology
  • Basic Botanical Terminology
  • Woody Plant Morphology
  • Grass Morphology
  • Sedge/Rush Morphology

Vegetation Identification for Wetland Delineation: North - Day 1 (Wallkill)

8:00am - 8:30am: Reception, Coffee/Refreshments, Registration
8:30am - 9:00am: Introductions, Introduction to the Course, Overview of References
9:00am - 10:00am: Review of Diagnostic Plant Characteristics
10:00am - 10:15am: Break
10:15am - 11:45am: Introduction to the Use of Field Guides for Plant Identification (Newcomb's Wildflower Guide and Field Guide to Nontidal Wetland
Identification
)
11:45am - 12:15pm: Lunch (in classroom)
12:15pm - 4:00pm: Use Field Guides to Identify Plants in and around Wetlands - High Point State Park and Wallkill National Wildlife Refuge (if time permits)
4:00pm - 4:30pm: Return to classroom and wrap-up

Vegetation Identification for Wetland Delineation: North - Day 2 (Basking Ridge)

8:00am - 8:30am: Coffee/Refreshments
8:30am - 9:30am: Lecture on plants characteristic of freshwater wetlands in northern New Jersey and New England
9:30am - 12:00pm: Use Field Guides to Identify Plants in and around Wetlands - Somerset County Environmental Center (SCEC)
12:00pm - 12:45pm: Lunch (in classroom)
12:45pm - 4:00pm: Use Field Guides to Identify Plants in and around Wetlands - SCEC and Great Swamp National Wildlife Refuge
4:00pm - 4:30pm: Return to classroom and wrap-up

* Note that field sites are subject to change due to site availability.

This wetland vegetation identification course is designed for anyone who wants to gain experience identifying wetland plants, including:

  • Arborists and Forestry Technicians
  • Biologists
  • Ecologists
  • Engineers
  • Environmental Scientists, Environmental Consultants, and Environmental Planners
  • Geologists and Hydrogeologists
  • GIS Specialists
  • Landscape Architects and Landscape Designers
  • Land Surveyors
  • Wetland Delineators and Wetland Scientists

Comments from Past Students about this Vegetation Identification for Wetland Delineation course:

"It was very hands on. Definitely helped me improve my skills with keying out different species. Was able to become more familiarized with some trees."
- Jen Reed, Ecologist

"It gives you a good, general education about local wetland vegetation which can be built upon."

"The site walks were very hands-on and very helpful."

"I found many more species that I can use to make my identification of wetlands more complete."

"Great introduction to plant species found in our area."

"Found everything to be useful and informative."

Ralph Tiner, M.S., M.P.A., SWS Fellow has over 40 years of practical experience in wetland delineation and is a nationally recognized authority in the field. He recently retired from the U.S. Fish & Wildlife Service where he directed wetland mapping in the Northeast United States as part of the U.S. Fish & Wildlife Service's National Wetlands Inventory (NWI). He is a nationally recognized expert on wetland delineation and has been actively involved in improving wetland delineation techniques for decades. In addition, he was compiler and principal author of the Federal Interagency Wetland Delineation Manual, which was published in 1989 and is the standard for identifying and delineating wetlands in New Jersey.

Ralph has written extensively on the subject of wetlands and is the author of several field guides including: Field Guide to Non-tidal Wetland Identification, Maine Wetlands and Their Boundaries, A Field Guide to Coastal Wetland Plants of the Northeastern United States, and In Search of Swampland, as well as an update of the Wetland Indicators book entitled Wetland Indicators: A Guide to Wetland Formation, Identification, Delineation, Classification, and Mapping. His most recent books are: Tidal Wetlands Primer: An Introduction to Their Ecology, Natural History, Status, and Conservation and Remote Sensing of Wetlands: Applications and Advances (for which he is senior editor and authored several chapters).

In addition to writing about wetlands, he has been teaching wetland identification and delineation courses through the Rutgers Office of Continuing Professional Education Office since the mid-1980s.

Comments from Past Students about Ralph Tiner:

  • "Ralph is the dude! Entertaining and excellent teacher. Ralph has a deep knowledge of wetlands and much more, is a joy to listen to."
    -Thomas D'Angelo, Environmental Consultant
  • "Very knowledgeable about plants and wetlands in general, entertaining teaching style."
  • "Patient, great at guiding field exercises."
  • "Great expertise and hands on experience."
  • "Mr. Tiner is very knowledgeable and friendly in his teaching methods."

Jump-Start Your Career with a Rutgers Wetland Certificate!

Promote your education and experience in wetland plant identification and delineation -- earn the nationally recognized Rutgers Wetland Delineation Certificate!

This certificate program consists of 6 days of training: our 2-day Vegetation Identification course (North or South sessions ONLY Winter and Tidal Plants are NOT part of the certificate series) and our 4-day Methodology of Delineating Wetlands course.

Participants must also complete the take-home exam with a score of 70% or better in order to earn the certificate.

NOTE: If you are planning to earn the Wetland Delineation Certificate, we require that you complete Vegetation Identification prior to attending the Methodology of Delineating Wetlands class.

Vegetation Identification Course - North: Photo Slideshow

The May 19-20, 2020 offering of this course was approved for the following credits. We will reapply for similar credits the next time the course runs, but we cannot guarantee credit approval for future offerings.

In addition to 1.6 Rutgers CEUs, this wetland training course is approved for the following credits:

Certified Public Works Managers - 5 Technical, 5 Management

Landscape Architecture Continuing Education System (LA CES) Credits - 16 hours

NJ Landscape Architects - 12 hours

NJ Professional Engineers - 12 Continuing Professional Competency (CPC) credits

NY Landscape Architects - 4 hours CL 10 hours EA

NY Professional Engineers - 12 hours

NY Land Surveyors - 12 hours

Society of Wetland Scientists Professional Certification Program (SWSPCP) - Vegetation Identification for Wetland Delineation: North has been pre-approved for 0.8 equivalent semester hours by the SWSPCP as meeting standards for content and instruction toward SWSPCP Professional Certification or SWSPCP Professional Certification Renewal. Approval per course is calculated based upon 15 hours of contact time per credit. Click here for more information about the Society of Wetland Scientists Professional Certification Program (SWSPCP).

ATTENTION HEALTH OFFICERS AND REGISTERED ENVIRONMENTAL HEALTH SPECIALISTS: Rutgers University, NJAES, Office of Continuing Professional Education has been approved by the New Jersey Department of Health as a provider of NJ Public Health Continuing Education Contact Hours (CEs). Participants who complete this education program will be awarded 13.0 NJ Public Health Continuing Education Contact Hours (CEs).

Society of American Foresters - Pending

The Wildlife Society - 12 credits

There are 2 Required Textbooks for this Course:

1. Newcomb's Wildflower Guide [ISBN 0316604429] by Lawrence Newcomb - $25.00 (You may purchase this book on your own or through our office with your registration.)

2. Field Guide to Nontidal Wetland Identification by R.W. Tiner - $50.00 (This book is only available through our office.)

Multi-Course Registration Fee

Save when you register now for this course and Methodology for Delineating Wetlands!


Contents

  • 1 Distribution
  • 2 Evolution
    • 2.1 Photosynthesis in Aquatic Plants
    • 2.2 Buoyancy Adaptations
    • 2.3 Terrestrial Plants in Aquatic Environments
  • 3 Classification of Macrophytes
    • 3.1 Emergent
    • 3.2 Submerged
    • 3.3 Floating-leaved
    • 3.4 Free-floating
  • 4 Morphological classification
  • 5 Functions of macrophytes in aquatic system
  • 6 Uses and importance to humans
    • 6.1 Food crops
    • 6.2 Bioassessment
    • 6.3 Potential sources of therapeutic agents
  • 7 See also
  • 8 References
  • 9 External links

The principal factor controlling the distribution of aquatic plants is the depth and duration of flooding. However, other factors may also control their distribution, abundance, and growth form, including nutrients, disturbance from waves, grazing, and salinity. [9] A few aquatic plants are able to survive in brackish, saline, and salt water. [6]

Aquatic plants have adapted to live in either freshwater or saltwater. Aquatic vascular plants have originated on multiple occasions in different plant families [6] [10] they can be ferns or angiosperms (including both monocots and dicots). The only angiosperms capable of growing completely submerged in seawater are the seagrasses. [11] Examples are found in genera such as Thalassia and Zostera. An aquatic origin of angiosperms is supported by the evidence that several of the earliest known fossil angiosperms were aquatic. Aquatic plants are phylogenetically well dispersed across the angiosperms, with at least 50 independent origins, although they comprise less than 2% of the angiosperm species. [12] Archefructus represents one of the oldest, most complete angiosperm fossils which is around 125 million years old. [13] These plants require special adaptations for living submerged in water or floating at the surface. [13]

Although most aquatic plants can reproduce by flowering and setting seeds, many have also evolved to have extensive asexual reproduction by means of rhizomes, turions, and fragments in general. [7]

Photosynthesis in Aquatic Plants Edit

Due to their underwater environment, aquatic plants have limited access to carbon and experience reduced light levels. [14] Aquatic plants have DBLs (diffusive boundary layers) that vary based on the leaves' thickness and density. DBLs are the main factor responsible for the lack of carbon fixation in aquatic plants. [14] Due to this reduced ability to collect nutrients, aquatic plants have adapted various mechanisms to maximize absorption.

In floating aquatic plants, the leaves have evolved to only have stomata on the top surface due to their non-submerged state. [15] Gas exchange primarily occurs through the top surface of the leaf due to the stomata’s position, and the stomata are in a permanently open state. Due to their aquatic surroundings, the plants are not at risk of losing water through the stomata and therefore face no risk of dehydration. [15] For carbon fixation, some aquatic angiosperms are able to uptake CO2 from bicarbonate in the water, a trait that does not exist in terrestrial plants. [14] Angiosperms that use HCO3- can maintain pH and keep CO2 levels satisfactory, even in basic environments with low carbon levels. [14]

Buoyancy Adaptations Edit

Due to their environment, aquatic plants experience buoyancy which counteracts their weight. [16] Because of this, their cell covering are far more flexible and soft, due to a lack of pressure that terrestrial plants experience. [16] Green algae are also known to have extremely thin cell walls due to their aquatic surroundings, and research has shown that green algae is the closest ancestor to living terrestrial and aquatic plants. [17] Terrestrial plants have rigid cell walls meant for withstanding harsh weather, as well as keeping the plant upright as the plant resists gravity. Gravitropism, along with phototropism and hydrotropism, are traits believed to have evolved during the transition from an aquatic to terrestrial habitat. [18] [19] Terrestrial plants no longer had unlimited access to water and had to evolve to search for nutrients in their new surroundings as well as develop cells with new sensory functions, such as statocytes.

Terrestrial Plants in Aquatic Environments Edit

There have been multiple studies regarding the physiological changes that terrestrial plants undergo when submerged due to flooding. When submerged in an aquatic environment, new leaf growth from terrestrial plants has been found to have thinner leaves and thinner cell walls than the leaves on the plant that grew while above water, along with oxygen levels being higher in the portion of the plant grown underwater versus the sections that grew in their terrestrial environment. [20] This is considered a form of phenotypic plasticity as the plant, once submerged, experiences changes in morphology better suited to their new aquatic environment. [20] However, while some terrestrial plants may be able to adapt short-term to an aquatic habitat, there is no guarantee that the plant will be able to reproduce underwater, especially if the plant usually relies on terrestrial pollinators.

Based on growth form, macrophytes can be characterised as:

  • Emergent
  • Submerged
    • Rooted: rooted to the substrate
    • Unrooted: free-floating in the water column
    • Attached: attached to substrate but not by roots
  • Floating-leaved
  • Free-floating [21]

Emergent Edit

An emergent plant is one which grows in water but pierces the surface so that it is partially in air. Collectively, such plants are emergent vegetation.

This habit may have developed because the leaves can photosynthesis more efficiently in air and competition from submerged plants but often, the main aerial feature is the flower and the related reproductive process. The emergent habit permits pollination by wind or by flying insects. [22]

There are many species of emergent plants, among them, the reed (Phragmites), Cyperus papyrus, Typha species, flowering rush and wild rice species. Some species, such as purple loosestrife, may grow in water as emergent plants but they are capable of flourishing in fens or simply in damp ground. [23]

Submerged Edit

Submerged macrophytes completely grow under water with roots attached to the substrate (e.g. Myriophyllum spicatum) or without any root system (e.g. Ceratophyllum demersum). Helophytes are plants that grows in a marsh, partly submerged in water, so that it regrows from buds below the water surface. [24] Fringing stands of tall vegetation by water basins and rivers may include helophytes. Examples include stands of Equisetum fluviatile, Glyceria maxima, Hippuris vulgaris, Sagittaria, Carex, Schoenoplectus, Sparganium, Acorus, yellow flag (Iris pseudacorus), Typha and Phragmites australis. [24]

Floating-leaved Edit

Floating-leaved macrophytes have root systems attached to the substrate or bottom of the body of water and with leaves that float on the water surface. Common floating leaved macrophytes are water lilies (family Nymphaeaceae), pondweeds (family Potamogetonaceae). [25]

Free-floating Edit

Free-floating macrophytes are aquatic plants that are found suspended on water surface with their root not attached to substrate, sediment, or bottom of the water body. They are easily blown by air and provide breeding ground for mosquitoes. Example include Pistia spp commonly called water lettuce, water cabbage or Nile cabbage. [25]

The many possible classifications of aquatic plants are based upon morphology. [6] One example has six groups as follows: [26]

  • Amphiphytes: plants that are adapted to live either submerged or on land
  • Elodeids: stem plants that complete their entire lifecycle submerged, or with only their flowers above the waterline
  • Isoetids: rosette plants that complete their entire lifecycle submerged
  • Helophytes: plants rooted in the bottom, but with leaves above the waterline
  • Nymphaeids: plants rooted in the bottom, but with leaves floating on the water surface
  • Pleuston: vascular plants that float freely in the water


Hydrophytic Vegetation

Wetland plants, or hydrophytic "water loving" vegetation, are those plants which have adapted to growing in the low-oxygen (anaerobic) conditions associated with prolonged saturation or flooding. These plants have adapted to anaerobic soil conditions by evolving alternative methods of collecting oxygen such as the hypertrophied lenticels in the bark of speckled alder the hollow stems of rush and grass species and the air filled cells (aerenchyma) in the roots of cattails.

Cattails

Plant species vary in their tolerance of wetland conditions. The following are indicator categories of plants as assembled by the U.S. Fish and Wildlife Service in the National List of Plant Species that Occur in Wetlands: Northeast (Region 1). The National List reflects the range of estimated probabilities (expressed as a frequency of occurrence) of a species occurring in wetland versus non-wetland across the entire distribution of the species. The indicator categories include:

  • Obligate Wetland (OBL). Occur almost always (estimated probability greater than 99%) under natural conditions in wetlands.
  • Facultative Wetland (FACW). Usually occur in wetlands (estimated probability 67%-99%), but occasionally found in non-wetlands.
  • Facultative (FAC). Equally likely to occur in wetlands or non-wetlands (estimated probability 34%-66%).
  • Facultative Upland (FACU). Usually occur in non-wetlands (estimated probability 67%-99%), but occasionally found in wetland (estimated probability (1%-33%).
  • Obligate Upland (UPL). Occur in wetlands in another region, but occur almost always (estimated probability greater than 99%) under natural conditions in non-wetlands in the region specified. If a species does not occur in wetlands in any region, it is not on the National List.

Obligate wetland plants include duckweed, water lily, pickerel weed, cattails, wooly sedge, soft-stem bulrush, royal fern, and water horsetail. Obligate upland plants include White pine, White clover, Virginia creeper, Christmas fern, and Ground ivy. Red maple, Poison ivy, Switchgrass, and Alpine violet are examples of facultative plants. Below are some examples of plants commonly found in Vermont wetlands.

Buttonbush

Spotted Joe Pye Weed

Silver Maple


4 Introduction to Plants for Difficult Planting Situations

Few landscapes and gardens will contain the perfect planting conditions. Environmental stress from variable combinations of light and moisture levels, exposure to wind and cold, soil characteristics, site slopes and drainage can create difficult situations for planting. Some plants will be better suited to tolerate environmental stress because of morphological and physiological adaptations developed in their native habitat. For example, Berberis buxifolia (box leaf barberry), Gleditsia triacanthos f. inermis (thornless honey locust), and Ginkgo biloba (maidenhair tree, ginkgo) are able to tolerate a fairly wide range of planting conditions. When planting in difficult situations such as the examples described below, select plants from similar habitats that are naturally adapted to grow under the existing conditions.

Sunny arid conditions

Environmental stress associated with arid (xeric) conditions can severely limit plant growth. Climate characteristics include full light exposure, high summer temperatures, low and unpredictable precipitation, and low humidity with drying winds. Soils with poor structure, minimal organic matter or soil biology and low water holding capacity and nutrient availability are common in arid conditions. Where hardiness is a limiting factor for plant selection, local regional native plants adapted to the existing climate, soils, and moisture regimes are often the most suitable choice.

Shade

Shaded areas that may seem problematic are in fact ideal for plants that occur naturally in habitats with low light, such as woodlands and ravines. There are many shrubs, trees, climbers, bulbs, ferns, and ground cover plants that either tolerate or prefer partial to full shade. For example, evergreen species and cultivars of Rhododendron spp. prefer deep to part shade while Rhododendron Northern Lights Group (azalea) prefers full sun to part shade. Characteristics of shade plants such as branched habits, two-ranked leaf arrangement, and broad, thin leaf blades are suited to capture available light. A strategy of some herbaceous plants, such as Crocus cvs. (crocus) is to emerge early, flower, set seed, and die back to resting structures before tree and shrub leaves fill in completely. Some shade tolerant trees, such as Tsuga heterophylla (western hemlock) and Acer saccharum (sugar maple) will germinate and grow as understory species until openings in the canopy allow them to grow to full size.

Dry soil

Dry shade

Wetlands

Natural wetlands with soil that is permanently or seasonally saturated often have anaerobic (low oxygen) conditions. Wetlands are typically vegetated with hydrophytic plants that are adapted to grow wholly or partially in water. Some hydrophytic species float on the surface of water, while others are completely submerged. Emergent species that root in soil underwater and grow shoots up and out of the water are usually found along the shoreline or margin of a wetland.

Compacted soils

Compacted soils are common in urban areas that undergo construction damage, or repeated machinery use and foot traffic. Damage to soil structure from tilling or working heavy clay and loam soils when they are too wet or frozen, and crusting of bare soils from the impact of rainfall contribute to compaction. As soil particles become densely packed together pore space is reduced and the movement of air, water, organisms, and plant roots is impeded. Once compacted, poor soil drainage, water logging, low oxygen, and hard surface conditions inhibit plant root growth. Plants symptoms may include poorly formed or rotted roots, stunted growth, discolored leaves, and drought stress.

Slopes

Sloped embankments and hillsides can be difficult planting situations. Successful plant growth will be influenced by soil type, the north to south aspect, the amount of rainfall, and the degree of incline and length of the slope. Steeper slopes increase the risk of erosion and soil loss that exposes roots or buries small plants. In addition, the run off of sediment from eroded slopes can adversely affect drainage systems and waterways that connect to fish habitat.

Planting slopes with grasses and shrubs is an effective way to protect soil and prevent erosion. Fast-growing, adaptable species with dense fine roots that hold the soil together and take up water help stabilize slopes and keep soil in place. Complete vegetation coverage will reduce the impact of rainfall and the potential for soil disturbance and erosion. Methods such as planting pockets and terraced steps will slow surface run off and facilitate the infiltration of irrigation for plant establishment.


1.4: Introduction to Plants for Difficult Planting Situations

  • Contributed by Michelle Nakano
  • Faculty (Horticulture) at Kwantlen Polytechnic University
  • Sourced from KPU Zero Textbook Cost Program

Few landscapes and gardens will contain the perfect planting conditions. Environmental stress from variable combinations of light and moisture levels, exposure to wind and cold, soil characteristics, site slopes and drainage can create difficult situations for planting. Some plants will be better suited to tolerate environmental stress because of morphological and physiological adaptations developed in their native habitat. For example, Berberis buxifolia (box leaf barberry), Gleditsia triacanthos f. inermis (thornless honey locust), and Ginkgo biloba (maidenhair tree, ginkgo) are able to tolerate a fairly wide range of planting conditions. When planting in difficult situations such as the examples described below, select plants from similar habitats that are naturally adapted to grow under the existing conditions.

Sunny arid conditions

Environmental stress associated with arid (xeric) conditions can severely limit plant growth. Climate characteristics include full light exposure, high summer temperatures, low and unpredictable precipitation, and low humidity with drying winds. Soils with poor structure, minimal organic matter or soil biology and low water holding capacity and nutrient availability are common in arid conditions. Where hardiness is a limiting factor for plant selection, local regional native plants adapted to the existing climate, soils, and moisture regimes are often the most suitable choice.

Shallow, extensive root systems allow species such as Rudbeckia fulgida (black-eyed Susan) to survive in drought and poor soil conditions. Plant characteristics such as small, compound, and modified leaves and stems, and light or gray colored leaves with hairy or waxy surfaces reflect sunlight, moderate the temperature at the leaf surface, and reduce water loss. Achillea filipendulina ‘Gold Plate’ (Gold Plate yarrow), Artemisia schmidtiana (silver mound), Festuca ovina glauca (blue fescue), Rosa rugosa (rugosa rose), and Abies concolor (white fir) are some examples of plants with these characteristics. Read more about plant adaptations at this link to Plant Adaptations to Arid Environments [New Tab] [1]

Shade

Shaded areas that may seem problematic are in fact ideal for plants that occur naturally in habitats with low light, such as woodlands and ravines. There are many shrubs, trees, climbers, bulbs, ferns, and ground cover plants that either tolerate or prefer partial to full shade. For example, evergreen species and cultivars of Rhododendron spp. prefer deep to part shade while Rhododendron Northern Lights Group (azalea) prefers full sun to part shade. Characteristics of shade plants such as branched habits, two-ranked leaf arrangement, and broad, thin leaf blades are suited to capture available light. A strategy of some herbaceous plants, such as Crocus cvs. (crocus) is to emerge early, flower, set seed, and die back to resting structures before tree and shrub leaves fill in completely. Some shade tolerant trees, such as Tsuga heterophylla (western hemlock) and Acer saccharum (sugar maple) will germinate and grow as understory species until openings in the canopy allow them to grow to full size.

T here is a wide array of ornamental plants suitable for planting in partial to full shade. Examples of ferns are Athyrium niponicum var. pictum (Japanese painted fern), and Matteuccia struthiopteris (ostrich fern). Shrubs for shade include Aucuba japonica (Japanese aucuba), Kalmia latifolia (mountain laurel), Kerria japonica (Japanese kerria), and Leucothoe fontanesiana ‘Rainbow’ (Rainbow leucothoe). Shade tolerant ground covers include Pachysandra terminalis (Japanese spurge) and Sarcococca hookeriana var. humilis (dwarf sweet box). The woodland understory tree, Cornus florida (Eastern flowering dogwood, pink flowering dogwood) is adapted to growing in partial shade. Learn more about shade gardening at this link to RHS Shade Gardening [New Tab] [2]

Dry soil

Multiple factors can contribute to dry soil conditions on a site. Soils with high sand or aggregate content that drain quickly move available water below the plant root zone, and surface slopes with rapid runoff reduce water infiltration into the soil. Overhead structures that block rainfall, such as building eaves or tree canopies with competing roots below ground can also create dry areas. While few plants will survive in permanently dry areas, drought tolerant native and garden plants can flourish in dry soil once established. Examples include ground covers, Arctostaphylos uva-ursi (bearberry, kinnikinnick) and Thymus serpyllum (mother of thyme), and herbaceous perennials, Arabis caucasica (rock cress) and Echinops bannaticus (globe thistle). A few examples of adapted deciduous shrubs and trees are Chaenomeles japonica (flowering quince), Crataegus laevigata cvs. (English hawthorn), Pyrus calleryana (ornamental pear) and Quercus robur (English oak). A conifer example, Juniperus virginiana (eastern red cedar) is tolerant of dry soil. Read more about suitable species for dry soil conditions at this link to Drought Tolerant Plants For Your Garden [New Tab] [3] .

Dry shade

A combination of shade and dry soil can create a difficult planting situation. Dry shade is typically found under tree canopies where dense fibrous roots close to the surface compete with other plants for water. While plants will not survive extended periods of drought without some watering, there are some such as Berberis spp. that will tolerate dry shade once they are properly established. Alchemilla mollis (lady’s mantle), Epimedium hybrid cvs. (hybrid barrenwort), and Pachysandra terminalis (Japanese spurge) are suitable herbaceous ground covers for planting in dry shade. Learn about some practical approaches to planting in dry shade at this link to RHS The Garden Dry Shade [New Tab] [4]

Wetlands

Natural wetlands with soil that is permanently or seasonally saturated often have anaerobic (low oxygen) conditions. Wetlands are typically vegetated with hydrophytic plants that are adapted to grow wholly or partially in water. Some hydrophytic species float on the surface of water, while others are completely submerged. Emergent species that root in soil underwater and grow shoots up and out of the water are usually found along the shoreline or margin of a wetland.

While the roots of many garden plants would rot when deprived of oxygen, hydrophytic plants are suitable choices for sites with water features as well as low areas with seasonal poor drainage or a high water table. Examples of herbaceous perennials suitable for wetland planting include Acorus gramineus ‘Variegatus’ (variegated sweet flag), and Matteuccia struthiopteris (ostrich fern). Aronia melanocarpa (black chokeberry), and Sambucus nigra (elderberry) are adaptable deciduous shrubs for wet conditions as are the deciduous trees Liquidambar styraciflua (American sweetgum), and Salix x sepulcralis var. chrysocoma (weeping willow). Depending on the available space, the large conifer Metasequoia glyptostroboides (dawn redwood) may be a suitable choice. Learn more at this link to RHS Gardening on Wet soils [New Tab] [5] .

Compacted soils

Compacted soils are common in urban areas that undergo construction damage, or repeated machinery use and foot traffic. Damage to soil structure from tilling or working heavy clay and loam soils when they are too wet or frozen, and crusting of bare soils from the impact of rainfall contribute to compaction. As soil particles become densely packed together pore space is reduced and the movement of air, water, organisms, and plant roots is impeded. Once compacted, poor soil drainage, water logging, low oxygen, and hard surface conditions inhibit plant root growth. Plants symptoms may include poorly formed or rotted roots, stunted growth, discolored leaves, and drought stress.

While the addition of compost is a long term solution for compacted garden soils, there are a number of species that are able to tolerate compacted soils reasonably well. For example, Catalpa speciosa (western catalpa) is a tough tree that tolerates poor soils and compaction as well as dry and wet soils. Acer saccharhinum (silver maple), Juglans nigra (black walnut), and Ulmus americana (American elm) tolerate some compaction as do Amelanchier canadensis (serviceberry), Juniperus communis ‘Green Carpet’ (Green Carpet juniper), and Matteuccia struthiopteris (ostrich fern). Read more about adapted species available at this link to Plants for Compacted soils [New Tab] [6]

Slopes

Sloped embankments and hillsides can be difficult planting situations. Successful plant growth will be influenced by soil type, the north to south aspect, the amount of rainfall, and the degree of incline and length of the slope. Steeper slopes increase the risk of erosion and soil loss that exposes roots or buries small plants. In addition, the run off of sediment from eroded slopes can adversely affect drainage systems and waterways that connect to fish habitat.

Planting slopes with grasses and shrubs is an effective way to protect soil and prevent erosion. Fast-growing, adaptable species with dense fine roots that hold the soil together and take up water help stabilize slopes and keep soil in place. Complete vegetation coverage will reduce the impact of rainfall and the potential for soil disturbance and erosion. Methods such as planting pockets and terraced steps will slow surface run off and facilitate the infiltration of irrigation for plant establishment.

Plants for slopes typically include native and ornamental grasses and low, spreading shrubs and ground covers that leave no areas of bare soil exposed to the elements. On hot, dry southern aspects, drought-tolerant shrubs and grasses such as Juniperus sabina ‘Tamariscifolia’ (tamarix juniper), Rosa rugosa (rugosa rose), and Festuca ovina glauca (blue fescue) are suitable options. Cooler, moister northern aspects are better suited for shade-tolerant understory shrubs and ground covers such as Gaultheria shallon (salal), and Pachysandra terminalis (Japanese spurge). Read more about slope gardening at this link to Pacific Horticulture Society Dry Slope Gardening in Seattle [New Tab] [7] .


Vegetation identification for wetland delineation: south

PUBLISHED ON August 28, 2019

NEW BRUNSWICK, N.J. — In this two-day course, you will learn plant identification principles and study diagnostic characteristics of species frequently encountered by wetland delineators in the Southern New Jersey region.

Along with hydric soils and hydrology, the presence of wetland plants is one of the primary factors involved in the identification of wetland areas and the delineation of wetland boundaries. Therefore, the ability to identify wetland plants and distinguish between upland and wetland plant species is an essential step in the wetland delineation process.


Watch the video: Plant Adaptation Types: Hydrophytic, mesophytic, Xerophytic adaptation and their features.


Previous Article

Photinia problems: the expert answers on the diseases of Photinia

Next Article

Do-it-yourself paludarium