Monday, October 6, 2014

Field trip to Black Oak Heritage Park, Windsor, Ontario

On September 6th, 2014 I participated in an annual field trip led by the Field Botanists of Ontario.  The trip was well attended and demonstrated some of the unique Black Oak savannah habitat found in the Windsor area.  A couple of rare plants were added to the official EARTHQUEST Plants of Ontario database such as provincially rare Tall Thoroughwort (Eupatorium altissimum).

Tall Thoroughwort
Photo: Dave Jolly

Special concern Shumard Oak (Quercus shumardii) was a new tree species for this section of the Park.  This contributes to the 500+ trees recorded for Essex county.  In fact, this oak species is one of the most dominant trees in Essex county within woodlots anywhere on the Clay plain in this region.  All other Shumard Oak reside primarily within Essex and Lambton counties extending eastward to Chatham-Kent.  Of the 10 sites were visited between June 18 and September 2, 2014 only these regional municipalities had Shumard Oak.  Previous Committee on the Status of Endangered Wildlife in Canada (COSEWIC) reports suggested that the range of this species reaches Niagara region, but these records have are now regarded as suspected hybrids based on visual identification traits; acorns, leaf buds, leaf shape, tomentum (tufts of hairs located on the leaf underside between the mid-rib and veins), etc.  To date, none of the Niagara region trees examined have been confirmed as 100% pure Shumard Oak.  Instead, they are likely hybrids between Red Oak (Quercus rubra) and Swamp Pin Oak (Quercus palustris) since both species were present at the sites investigated.  The resulting hybrid is Q. rubra x Q. palustris if it exhibits more Red Oak traits and Q. palustris x Q. rubra if it exhibits more Swamp Pin Oak traits.  Genetic studies would ultimately clear up any misconceptions about the true distribution of Shumard Oak in Canada.

New to the database was Swamp Lousewort (Pedicularis lanceolata), which was adjacent to a large patch of Colicroot (Aletris farinosa).  With the high biodiversity of  Tallgrass prairie mixed with Black Oak savannah species.  The most exciting discovery was a new record for Essex county of endangered Spotted Wintergreen (Chimaphila maculata) to add to the Ontario Recovery Strategy series.

Spotted Wintergreen
Photo: Dave Jolly