Promoting Prairie

 Today, June 4, is National Prairie Day. At least it is in the USA, but hasn't been recognized as such in Canada yet, which is unfortunate since tallgrass prairie is a significant habitat type throughout many provinces. Regular readers will know that I am a huge fan of tallgrass prairie.

The first three photos are representative of some of the 100+ prairies I have explored in the mid-western US, mostly in Missouri.

Diamond Grove Prairie

Golden Prairie

Treaty Line Prairie

These next two are from southwestern Ontario.

Island Prairie, Walpole Is

The following photo is of a small patch that occurs at Rondeau, and features an impressive stand of Butterfly Weed. It could arguably be called part of a Black Oak Savanna. The large Black Oak with its spreading limbs certainly fits the savanna theme.

Prairies are becoming increasingly recognized for their value beyond the species diversity they support. Certainly grassland birds are becoming quite rare, as are some of the multitude of invertebrates inhabiting them. But even more so, old growth grasslands, which means grasslands that have never been plowed, store huge amounts of carbon. An old growth grassland has enormous amounts of herbaceous material below the surface. Some high quality species have root systems that go 6 metres or more below ground.

Some of the rarest plants in Ontario occur in tallgrass prairie, or the closely related oak savanna. This first one, Tall Green Milkweed, only occurs in one location in Ontario.

Eastern Prairie White-fringed Orchid is technically not limited to prairie, but usually has its greatest abundance there. It is a Species At Risk (SAR).

Closely related, but now gone from Canada, is the Yellow-fringed Orchid.

Giant Swallowtails, at one time considered a candidate as a SAR is seen feeding on Ironweed, a species limited to prairies.

Ironweed

An endangered species and therefore a SAR, is Slender Bush Clover.

Rough Blazing-star is a SAR.

Its more common relative, Tall Blazing-star, can be quite dominant in some limited prairies.

Another orchid, Purple Twayblade, is a SAR.

Pink Milkwort, next, is limited to only a couple of prairie sites in Ontario.

Goat's-rue is also a SAR, being limited in Ontario to only a couple of places.

This next photo shows one of the largest populations of a rare prairie species, Colicroot. Unfortunately this prairie patch was completely destroyed to allow for an expanded highway development.

A Cylindrical Blazing-star meadow graces some of the beach dune area of Rondeau. Although technically not a tallgrass prairie in the normal sense, it is a variation of it, and supports mostly tallgrass prairie plant species.

Prairie and savanna can occur in the same area, as is the case for this scene from Ojibway Prairie Provincial Nature Reserve in Windsor, which features a tall candelabra type plant called Culver's root

A little more on the oak savanna side of things is this scene featuring a Black Oak savanna at Rondeau Provincial Park.

Tallgrass Prairie and Black Oak Savanna: two of the most endangered habitats in Ontario. I encourage you to get out to explore and appreciate them!

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Milkweeds (and Monarchs) have a new lease on life!

Probably many of you reading this are aware of recent changes to the Noxious Weed list of Ontario. Up until this spring milkweeds, which includes the entire genus of Asclepias, were on this list and ultimately at risk. Landowners were obligated to remove them from their property, and if they didn't, the weed inspector could authorize someone else to do it for you and send you the bill!

In reality, there was only one species of milkweed that was really any problem, and that species was Common Milkweed (Asclepias syriaca). It could get quite aggressive especially on the farming landscape, as it thrives on disturbed sites. But the list of Noxious Weeds was compiled years before there were chemical controls and other methods of tilling that helped keep it from being too problematic in the agricultural setting.

Asclepias syriaca

The Monarch butterfly is highly dependent on milkweeds, especially Common Milkweed, as the adults lay eggs on the milkweed's leaves and the caterpillars consume the leaves. The milky sap that the caterpillars ingest as they eat the leaves is what makes eating the caterpillars so distasteful to predators. The very distinctive colours of the caterpillar serve as ample warning to caterpillar-eating birds to beware.....they are not a tasty meal!

In recent years, as the Monarch butterfly declined and became legally listed provincially and nationally as a Species At Risk (SAR), there was a conflict with retaining milkweeds on the Noxious Weed list and requiring landowners to destroy the critical plant of a SAR. So it was a major, yet long overdue, event earlier in 2014 when milkweeds were removed from that list.

With that as background, let me introduce you to eight of the other nine milkweeds of Ontario (The 10th species, Four-leaved Milkweed [Asclepias quadrifolia], is extremely rare and in Ontario is currently found only in one or two places in the east. I have yet to see it).

Swamp Milkweed (Asclepias incarnata) is a tall species that is commonly found in wet areas, as its name suggests. Wetlands, roadside ditches and the like are great places to see this one. Its reddish purple flowers and relatively long narrow leaves, as well as the habitat, are useful characteristics.

Asclepias incarnata

Poke Milkweed (Asclepias exaltata) is an uncommon species most often found along woodland edges. It has wide leaves, and pinkish white downward hanging clusters of flowers.

Asclepias exaltata

Butterfly Milkweed (Asclepias tuberosa) is probably the most distinctive milkweed of all! It is found in grassy woodland openings, in prairies and on grassy sandy beaches.

Asclepias tuberosa

Green Milkweed (Asclepias viridiflora) is not a plant that many people would recognize as a milkweed. In fact most people would walk by it and not give it much thought at all. This next photo is of a fairly robust plant along a sandy trail through the southeast beach of Rondeau, with closer views following.

Asclepias viridiflora

Whorled Milkweed (Asclepias verticillata) is generally not common anywhere in Ontario, but where it does occur, can be fairly abundant. The leaves are quite narrow which together with its white flowers, separate it from all other Ontario milkweeds.

Asclepias verticillata

All of the preceding species occur or formerly occurred at Rondeau. Whorled Milkweed has not been seen for at least two decades.

Prairie or Sullivant's Milkweed (Asclepias sullivantii) is restricted in Ontario to the extreme southwest. It grows in some of the better quality tallgrass prairies, and also may be found along some highway road allowances where the vegetation may have some structural characteristics of a prairie. It looks a lot like Common Milkweed, but the underside of the leaves are not hairy, the leaves are more upright and the main leaf veins are more purplish.

Asclepias sullivantii

Purple Milkweed (Asclepias purpurascens) has vivid, deep purple flowers. It is a plant of some of the best quality tallgrass prairie and savanna in southwestern Ontario.

Asclepias purpurascens

One of the rarest milkweeds in Ontario is Tall Green Milkweed (Asclepias hirtella). To date in Ontario it has only been found in the tallgrass prairies of the Ojibway Prairie area in Windsor, and probably totals less than two dozen plants. It is a relatively common species in the mid-western tallgrass prairies, however. The next photo is one I took on a wonderful Missouri prairie in 2007, whereas the second one was taken on film in the 1990s from a small population in the Ojibway area.

Asclepias hirtella

So get out and enjoy some of our native milkweeds....the butterflies sure do!

Here is a bit of additional info: currently there are two stamps for sale via Canadian Postal outlets.....one of a Monarch adult for 22 cents, and a Monarch larva for 2 cents