Wednesday, July 2, 2014

Long-term success with smooth brome eradication on a prairie remnant

Although it may take a while, it is possible to replace smooth brome with a high diversity of native prairie species. In the early days of our restoration work on the road-cut of our south-facing slope, while we were concentrating on brush/tree removal and wild parsnip/sweet clover control, smooth brome got started. Due to ignorance, we ignored it! Within a few years it had become well established, and native species had become scarce.

In contrast to the south slope as a whole, which was (and is) a fairly good prairie remnant, the road cut was virtually barren with only a few "good" species. I assume this is a legacy of road construction, since Pleasant Valley Road was re-aligned sometime after World War II. Also, the road cut is steeper than the rest of the hillside, and hence more xeric.

In 2005, five years after we had cleared the road cut and the whole south slope, we carried out an eradication of smooth brome on the road cut by early-season glyphosate spraying. This technique is described in some of my earlier posts. The photo here shows the spraying we did on April 14, 2005.


Pleasant Valley Road being sprayed with glyphosate by the local Co-op in 2005. The green is virtually "pure" smooth brome.
About a week after the road cut was sprayed, it was hand-planted with a complete prairie mix. Some of the species appeared within a year or two, but many of them took some years to get established. Although a few plants of lead plant were found after 6-7 years, this year, 9 years later, we now have dozens of plants. Since lead plant is a fairly conservative prairie species (C value of 7), and a virtual indicator of dry prairies, it is satisfying to see so many now well established.

Lead plant (Amorpha canescens) now well established on the Pleasant Valley Road cut.
Yesterday my brief survey came up with the following species now established on this road cut. Since this wasn't an exhaustive survey, I'm sure there are more.

Latin name
Common name
Amorpha canescens
Lead-plant
Andropogon gerardii
Big bluestem
Anemone cylindrica
Prairie thimbleweed
Asclepias tuberosa
Butterfly weed
Astragalus canadensis
Canada milk vetch
Baptisia alba
White wild indigo
Dalea purpureum
Purple prairie clover
Desmodium canadense
Showy tick-trefoil
Desmodium illinoense
Illinois tick-trefoil
Echinacea pallida
Pale purple coneflower
Erigeron strigosus
Daisy fleabane
Heliopsis helianthoides
Ox-eye sunflower
Kuhnia eupatorioides
False boneset
Lysimachia ciliata
Fringed loosestrife
Monarda fistulosa
Wild bergamot
Ratibida pinnata
Yellow coneflower
Rudbeckia hirta
Black-eyed Susan
Schizachyrium scoparium
Little bluestem
Silphium laciniatum
Compass plant
Sorghastrum nutans
Indian grass
Thalictrum dasycarpum
Purple meadow-rue
Tradescantia ohiensis
Common spiderwort
Verbena stricta
Hoary vervain

During the years since 2005, the road cut has only been managed by annual dormant season burns and brush control at about 3-4 year intervals.

This year brush on the whole south slope was controlled by basal bark treatment with our standard method, 20% Garlon 4 in bark oil.

Due to the steepness of the road cut, work there requires a bit of special skill. Thanks to Susan, Amanda, two Chris', Kathie, Heisley, Marci, Dan, Sara, Willis, and perhaps others for managing to stay upright while planting and doing careful brush control work!

No comments:

Post a Comment