Showy Orchis (Galearis spectabilis) Blooms at Rockcliff Farm

In early April, nearly one hundred Galearis spectabilis, the Showy Orchis, began to bud and bloom on a steep gorge within seventy five yards of the Wells house at Rockcliff Farm.  The most remarkable part of this orchid irruption is that a blooming Galearis spectabilis had not been seen in recent years.  It was not found during an extensive vegetation survey of Rockcliff Farm done in 2005, and had not been reported from the many wildflower walks conducted there over the past 10 years.  Below is a blooming Showy Orchis from this group.

Galearis spectabilis
Showy Orchis

So what were the circumstances that made this  sudden bloom possible?

One clue comes from observations made last year.  In early April 2016, a group of plants with two round, wide leaves were seen on the rich hardwood slopes of a steep-walled valley located about a mile from Rockcliff Farm.  One of these, with a developing bud, is pictured below.  In the photo, there appear to be three leaves because the plants are often right next to or on top of each other.  So there are actually two plants in the photo.

Galearis spectabilis
Showy Orchis
Basal Leaves and Bud

The plants were visited five days later to observe the bloom, but unfortunately deer had eaten the entire group of plants.  The same plant pictured above is shown below.

Galearis spectabilis
Showy Orchis
Plant Eaten by Deer

This year in early March, about 30 orchids were found in the same area.  They were covered with plastic deer screen to protect them from browsing.   In April they began to bud and bloom into typical Showy Orchis.

But what about the orchids at Rockcliff Farm, that were not protected against deer browsing because the orchids were not known to be there?  One possible explanation is the serious wildfire that occurred at the B. W. Wells S.R.A. in early March, just adjacent to Rockcliff Farm.  The fire started in the main power line due to a tree falling across electrical wires.  The fire burned down to the edge of the lake from both sides of the power lines along the road, and was hot enough to kill trees and destroy all shrubbery and ground cover.  Thus the hypothesis is that this fire destroyed most of the deer browse in this area, and the deer moved on to greener pastures, leaving the orchids unharmed.

In fact, over-abundant deer populations have been blamed for orchid declines, and reductions in deer density have been associated with surges in orchid populations.  (See Knapp, W. and Wiegand, R. 2014. Orchid (Orchidaceae) decline in the Catoctin Mountains, Frederick County, Maryland as documented by a long-term dataset. Biodiversity Conservation. Volume 23, Issue 8, pp. 1965-1976.)

Below, buds can be seen developing in two intertwined Showy Orchis.

Galearis spectabilis
Showy Orchis
Flower Buds

 

Galearis spectabilis
Showy Orchis
Flower Buds

The upper hood of the flower is formed by lateral petals and sepals.  The lower petal is large and white (a good landing place for bumblebees) and forms a spur at the rear.

Galearis spectabilis
Showy Orchis
Flowers

At the rear of the white lip is a hole that leads to a small nectar chamber (nectar reward).  Bumblebees can extend their tongues through the hole to reach the drop of nectar.  In the photo below, a small fly appears to have found the nectar.

Galearis spectabilis
Showy Orchis
Nectar Reward With Fly

Although Showy Orchis is very widespread, extending all the way from Canada to Georgia and into the Midwest, it is considered uncommon to rare in most of its range.

Herb Amyx

Advertisements
This entry was posted in Uncategorized and tagged , , , . Bookmark the permalink.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s