Experiments with Natives in The Meadows of Little Long Pond
On September 10, Tate Bushell, Director of Natural Lands of the Land and Garden Preserve (LGP), gave us an informative tour of the experiments they have been conducting over the past 5 years on how to introduce native plants into an already established meadow of mostly non-native grasses. For a detailed report that provides a lot of background on The Meadows of Little Long Pond, please see this excellent publication written by Tate.
Meadows in Maine
Tate started the tour by explaining that prairie, like we know from the midwestern states, is not a native ecosystem to Maine. In Maine the native habitat is primarily forest. Meadows are a remnant of our agricultural past and so it seems natural that they contain mainly plants that were brought from Europe by the first settlers. Open areas such as these will become forested over time if we don’t keep the woody vegetation at bay by periodic mowing. At LGP they value the history of the land and want to preserve the views that the historic meadows provide. However, they are interested in incorporating more native species to enhance habitat for native insects and other creatures that have evolved alongside the plant species native to Mount Desert Island but have little or no relationship to those from Europe.
Mowing
The topic of mowing came up early in the tour. When Tate arrived on the job 6 years ago, the meadows had been mowed annually. One of the first decisions he made was to suspend mowing in order to see which plants were being suppressed by annual mowing. Some areas have not been mown for 5 growing seasons and they have observed some woody plants moving in. They concluded that with their climate of relatively short, cool growing seasons right along the coast, they can maintain the values of an open landscape by mowing just once every 2-3 years.
Site Preparation
On the site were some particularly problematic, non-native, invasive stands of reed canary grass (Phalaris arundinaceae). These areas were targeted for trial plots as a way to control this grass and add diversity to the existing monoculture. We first visited a plot that had been rototilled repeatedly for 2 years. Before planting, loam was put down, and the area was planted with quart-sized plants that had been grown at the LGP greenhouse from seed. It was mulched with leaf mulch and wood chips. It has been weeded intermittently ever since to give the desired plants more space. Tate said that in retrospect the loam they had spread on this first plot wasn’t worth the weed seed that was in it.
For contrast we looked at an adjacent plot. This one had also been rototilled, but it had been target sprayed with herbicide (Roundup) when plants emerged (about 4 times per summer) and seeded in the fall. This plot, being several years behind the first, was filling in quickly.
When seeding a plot with natives, Tate gave the following advice:
Sow your seeds in the fall so they can go through the winter experiencing local conditions which are necessary for many native seeds to germinate.
It is a good idea to bulk up your seed mix with sand or cat litter to achieve uniform coverage when broadcasting.
Contact between the seed and bare soil is essential for good germination. Tate suggested renting a roller for this.
Since our group was generally opposed to using herbicide, we discussed some alternatives. Tate suggested that a sod cutter could be used to remove the turf which would eliminate sprouting and regrowth from roots chopped up by the rototiller. Smothering was also discussed and thought to be a solution for a smaller area. Plastic or cardboard could be used to smother the existing plants during the growing season. If cardboard is used for smothering prior to seeding, loam would be needed to top it or mulch could be used to weigh down the cardboard when planting plugs or potted plants.
The size of the plots is important. Tate used 30’ x 30’ plots which were large enough to prevent the edges of the existing meadow from encroaching on the plot. They mow around the perimeter of the plots occasionally during the summer to provide access for monitoring and weeding and help prevent encroachment. In some places they are attempting to “mow like crazy” to suppress some of the problematic plants.
Species notes
A few native plants that tend to seed into the plots that are not desired are common wrinkle-leaved goldenrod also known as rough-stem goldenrod (Solidago rugosa) and Canada goldenrod (Solidago canadensis). The reason for this is that they spread by underground roots and can be very aggressive which can result in almost a monoculture, reducing the plot’s diversity. Tate also mentioned that lance-leaved American aster (Symphyotrichum lanceolatus) can have the same problem, but that plant is not found near The Meadows. The main thing is do not include these in your seed mix! Fox sedge (Carex vulpinoidea) is easy to germinate that looks great early in the season, but tends to flop toward the end of the summer on some sites.
When thinking about a seed mix, Tate suggests using about 20 different species to ensure good diversity. Too few species might end up in failure. At LGP, they attempted to add a couple of meadow species that were noted in an 1894 inventory that were missing from a recent one. We searched for a couple of them, but did not find them in the seeded plots. They are fortunate at LGP have old documents to help guide their actions! Seed mixes should be tailored to site conditions. If you have clay soil like at LGP, species that are typically found in sandy soil like little blue stem (Schizachrium scoparium) will not thrive.
At LGP, they are also allowing shrubs to fill into some areas that might otherwise be prone to erosion, like along the edge of the pond. They will manage these for height to maintain the open appearance, but find that shrubs such as steeplebush (Spiraea tomentosa) and rhodora (Rhododendron canadense) can also be colorful and functional in a native meadow.
Other Challenges
Deer are a big challenge for getting certain species established. Perhaps the most difficult one is New England Aster (Symphyotrichum novae-angliae) which is heavily browsed. Another challenge is invasive species or the couple of aggressive natives mentioned earlier. Human and pet traffic which causes erosion is also a challenge at The Meadows of Little Long Pond.
We deeply thank Tate Bushell for his willingness and generosity to help us all benefit from the lessons he has learned through his experiments. While it might seem like a simple idea to plant natives into an existing meadow or lawn, we learned that it is not always easy and certainly not maintenance free.
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