Late Bloomers

It’s the time of year when, sadly, only a few wildflowers are still in bloom. As the summer rolls into August, the flowers that dazzled us in June and July wither and go to seed. This may be a small loss to us people, but there’s a huge group of animals that depend on blooming flowers for survival: insects.

Beeflies (Bobylius sp.) are adorable flies that specialize on drinking nectar.

A hairstreak butterfly drinks nectar from Stiff Goldenrod (Oligoneuron rigida).

A tiny, beautiful wasp sips nectar from Stiff Goldenrod.

A robber fly devours a wasp. Robber flies are agile predators that often target insects drawn to flowers.

A tree cricket munches on goldenrod petals.

A crab spider uses her camouflage to ambush pollinators in a goldenrod.

A bumblebee settles down for the night on Dotted Blazingstar (Liatris punctata).

Countless insects depend on flowers for nectar, pollen, and petals for food. They include bees, butterflies, beetles, wasps, tree crickets, ants, hemipterans,  thrips, and more. After plants, they are the the foundation of the food web. So what do they do in late summer when wildflowers are scarce?

Fortunately for our six-legged friends, there is a small group of flowers that bravely bloom in the heat and drought of August and September. In Gallatin County, the two most obvious are Dotted Blazingstar (Liatris punctata) and Stiff Goldenrod (Oligoneuron rigida).

Dotted Blazingstar (Liatris punctata) at Highland Glen Nature Preserve, Bozeman, MT.

Stiff Goldenrod (Oligoneuron rigida) at Lower Mount Ellis Trail, Bozeman, MT.

Dotted Blazingstar (Liatris punctata)

If you haven’t taken a close look at these plants, you’re missing out. Not just because they’re beautiful, but because their colorful petals often hold amazing dramas of sex and violence. In this post I am going to share one with you. First, let me introduce our protagonist: the American Jagged Ambush Bug (Phymata americana).

Look closely at any Stiff Goldenrod and you’re likely to find one or more of these bugs. Their bizarre shape and color help them  camouflage as they wait for pollinators to land for a drink. When pollinators come too close, ambush bugs snatch them up with their raptorial front legs (like those of a praying mantis). They subdue their prey, which are often much larger than themselves, by using their straw-shaped mouthparts to inject a paralyzing venom. Once subdued, ambush bugs contentedly sip the insides of their prey while resting on the flower.

Last August I was watching ambush bugs on Stiff Goldenrods at Mt. Ellis Trail when I noticed a female carrying around a small male. The males of some insect species have a habit of riding around on their mates as a way of preventing other males from mating with her. The reason for this soon became very clear to me. Without warning, a big, mean, alpha ambush bug came out of nowhere and tried to pull the little male right off the female! Click on the first photo below to watch the drama unfold:

Big Male arrives to steal Little Male’s mate.

Undaunted, Little Male hangs tight while Big Male climbs aboard.

Big Male attempts to pry Little Male off his mate.

Little Male bravely hangs on, so Big Male tries pulling to the right…

…forwards…

…and backwards.

Growing desperate, Big Male tries pulling on Little Male’s antenna. Ow.

Big male extends his mouthparts, perhaps trying to stab Little Male?

After three minutes of struggle, Big Male finally gives up! Little Male and his mate are left in peace.

Who knew the drama on a flower could match that of a nightclub! Stop to watch a late-blooming flower next time you see one, and maybe you’ll come back with a story of your own.  These flowers do a whole lot more than just make our meadows look pretty. (Click here to read a story I wrote about another pollinator-ambushing insect.)