Helping Rare Plants Become Common.

Have you ever seen the plant Golden seal, Hyrastis Canadensis or Ginseng, Panax quinquefolius in your woodlot or Twin leaf, Jeffersonia diphylla growing anywhere in the wild?  If your answer is no, you are not alone. These plants are members of a select list of plants in NYS, plants that are classified as threatened or extremely rare in the wild.

Some species of plants have limited populations in the wild because they only grow in unique habitats that restricts where these species can grow and those habitats may be very rare themselves. Some species have very specific requirements for reproduction or produce very little seed that limits their ability to reproduce.  Other species are rare because they are at the very extreme limits of their range in New York state.

These plants do not fall into any of those categories.  It appears there is a combination of two factors that explains why these plants are so uncommon. During the late 1800’s and early 1900’s New York State was only 20 to 25% forested according to a DEC web-page.  In comparison today New York State is about 65% forested. The majority of the land in NYS had been cleared for agriculture use sometime during the 1800’s.  The land was either used to grow crops or used as pasture to graze animals.  After the land was abandoned for agricultural purposes it gradually reverted to forest but many of the plant species that are normally present in an undisturbed forest were unable to recolonize those abandoned lands.  This was due to a lack of a local seed source or because of slow seed dispersal and colonization.

A century or more of human activity on a state wide scale has significantly altered and affected the plant communities that we see today iin our woodlands.  Land used to grow crops over many years would have their seed bank cleared of all forest species.  Forest which was commonly used to graze cattle, sheep and hogs would have most of the forest understory shrubs and forbs eliminated from the seed bank.  For plants to be able to recolonize those abandoned agricultural lands, plants had to find a place to survive and produce seed during the intervening years.  Plants might find a safe haven in out of the way places like hedgerows, ditches or remnant forest parcels.  These remnant patches would contribute seed to recolonize neighboring land but it all depended on the mechanism for seed dispersal, the type of habitat each species required and the distances the seed had to travel whether those plants could recolonize adjacent land. Those plants that did not survive in these isolated patches would be permanently absent from the surrounding habitat. 

The other factor that explains the rarity of some plant species is over collection and harvest by people.  Some plants like Ginseng and Golden seal have been used for medicinal purposes for centuries.  These plants have always been collected from the wild and utilized by people. Over many years of collecting these medicinal plants would have been over harvested to the point of eliminating local populations.  Commercial harvest for the herbal market has had a more significant and widespread impact that has led to large areas of the country being stripped of theses special plants. As populations of plants were completely removed from one woods or region the pressure on remaining populations would only increase. Once a population is eliminated there is no way for it to become reestablished other than by the good graces of man and no one was practicing any type of stewardship in those days.

Most of these plants can be grown quite easily from seed. Native plant nurseries grow Goldenseal and Twin leaf from seed.  Ginseng is also grown commercially from seed for the herbal market. Seed can be used to reintroduce these plants back into their natural habitat.  Seed can be collected from mother plants and planted in suitable woodland habitat to reestablish the plant in the wild.  This will make them more secure in the wild, help to preserve the genetic diversity of the species and add to the biodiversity of our woodlands.

Now your interest is piqued and you want to establish these plants into your own woods, but where do you find the seed?  The easiest way to get started is to buy a few starter plants from a local native plant nursery.  Plant them in your yard for ease of monitoring, in suitable habitat for each species and then wait for them to flower and set fruit. Plants tend to produce an abundance of seed to compensate for seed predators and inefficient seed dispersal so one plant can supply a large amount of seed. While you are waiting you can observe how the seed and fruit is produced, how the fruit develops over time as it matures and what it looks like at maturity. When the fruit matures collect it, remove the seeds and use it for planting. Sow the seed very soon after collecting where you want the plants to grow.  One good reference book on native plant propagation is William Cullina’s book Growing and Propagating Wildflowers or the web page http://whiteoaknursery.biz/restore/index.html. Ginseng and Goldenseal seed and roots may be purchased from members of the Empire State Ginseng Growers Association, PO Box 117, Freehold, NY 12431.

The seed of Ginseng, Goldenseal and Twin leaf are fairly easy to work with.  It helps that the seed tends to be fairly large.  Seed should be removed from the fruit and planted immediately or mixed with moistened potting mix for short term storage.  Plant the seed where you want the plants to grow and then be patient.  If you are lucky some seed may germinate the first spring but many of the seed may take two seasons or more to germinate.  Be patient and keep adding to the seed bank with new seed. Even after germination occurs the seedlings may be quite small the first year or two. These woodland plants tend to prefer fertile, moist well drained soils but any woodland soil with a deep layer of humus should be suitable.

 

Ginseng seed is produced in a cluster of bright red fruits on the end of a seed stalk. Crush the fruit to remove the seed prior to planting.  Goldenseal seeds are enclosed in a round pink colored fruit the size of a large marble.  Each fruit contains a number of seeds. Remove the seeds from the fruit by crushing and plant.  Twin leaf seeds are held in a thimble sized capsule with a hinged top at the end of the flower stalk.  When the seed matures the top of the capsule opens revealing rice sized brown seeds. Collect seed as it begins to turn dark brown.

Seed can be collected and used to introduce many types of woodland wildflowers both common and uncommon. A common pecies such as White trillium, trillium grandiflorum may be extremely abundant in some forests but completely absent in others.  You can harvest seed from a healthy trillium population and begin to establish a new population. Look for plants that should be present in your woods but are not there and consider whether to reintroduce them.  Just as important, if a plant is present but is limited in its distribution, harvest the seed and plant it in other areas a distance away from the existing population.  You will not only help to increase biodiversity in your woodland but help to conserve populations of native plant in the wild where they rightfully belong. There are only a few good rules to follow.  First make absolutely sure that the seed you are introducing is native and not a cultivar of a native plant or an exotic look alike.  Try to match the plants habitat requirement with your woodlot.  If the habitat is not suitable for the plant the seedlings will likely not survive.  There is no legal restrictions on collecting seed of native plants on your own property, get permission to collect seed or establish plants on private property and it is against the law to remove or collect anything from state lands.

Other species worthy of reintroduction are some of the native lilies, Lilium superbum, Turks cap lily, Lilium canandense, Canada lily but all of the native plants common and rare are deserving of your consideration for reintroduction.  This is nature gardening on a scale that can create new populations of native plants that are fulfilling their intended biological role and be self sustaining. What better way to give back to nature.

Jim Engel operates White Oak Nursery, a native tree and shrub nursery, and is actively involved in all aspects of habitat restoration.

 

by James P. Engel, © 2010

 

this page updated Feb 10, 2010