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Invasive Plants in the Conservatory Greenhouse

One of the many delights of being a volunteer at the U of M's Conservatory Greenhouse has been the constantly changing display of plants and projects. My shift this week included work on a new display of plants considered highly invasive in Minnesota.

The staff at the Conservatory Greenhouse have recently collaborated with another department called the Minnesota Invasive Terrestrial Plant and Pest Center (MITPPC). The partnership will introduce the subject of invasive plant species to the students and public guests at the Conservatory Greenhouse.

The purpose of the MITPPC, established in 2014, is to research the prevention, detection, and control of terrestrial invasive species in Minnesota. The Center has an informative and interesting website.

Recently added display of non-native plants highly invasive in Minnesota

Several examples of highly invasive plants were sent to the Conservatory Greenhouse for display from the MITPPC. My specific task this week was to re-pot some of the plants and relocate them within the Conservatory to a bench more visible to students and the public. As an example of the care taken to avoid the spread of these plants, the soil from the repotting activity had to be separately sequestered for sterilization to ensure live seeds weren't being released into into compost bins, which might subsequently spread far and wide.

As promised in a prior version of this blog post, here is the list of plants considered highly invasive in Minnesota. The list is limited to those plants on display at the greenhouse, it is not meant to be a list of all invasive plants in the state of Minnesota.

Frangula alnus (Buckthorn)

Miscanthus saccharifloria (amur silvergrass)

Salix x fragilis (crack willow)

Berberis x ottawensis (barberry 'silver miles')

Tamarix ramosissima (saltceder, or tamarisk)

Sorbaria sorbifolia (false spirea, false goats beard)

Elaeagnus angustifolia (Russian olive)

Gypsophilia paniculata (baby's breath)

Berberis thunbergia (Japanese barberry)

Typha angustifolia (narrowleaf cattail)

Reynoutria japonica (Japanese knotweed)

Euonymous alatus (burning bush, or winged spindle)

For more in-depth information, here is a link to a list of invasive terrestrial plants in Minnesota, gathered by the Minnesota Department of Natural Resources.

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