Relief from the July drought

A good bit of rain has finally come our way and it seems big hollow did not miss out.  Below are some photos taken at big hollow from the past couple of days.

 

Asclepias viridflora, in fruit

Now is a great time to see Allium cernuum (nodding onion) in bloom

Pearl Crestent (Phyciodes tharos)

Trichostema brachiatum (blue curls) have just started blooming with in the past week or so.

 Pycnanthemum sp. (mountain mint), as always, loaded with insect pollinators

A depauperate yet still senic limestone prairie (in Centre Co.)

I visited this prairie/barrens area today for the first time ever  during the growing season with the hope of finding more PA endagered prairie plants or just some not so common species.  With the exception of one forb everything I was able to detect in fall was what I saw today.  The most important forb being Solidago rigida, (seen in the pic. above at middle left) a state listed limestone prairie plant.  The population w/in a mile radius of this area contains several acres of grassland with abundant stands of this goldenrod throughout.  This area may well be the last stronghold for this important and attractive plant in the in the region if not the state.  The dominant graminoid was poverty grass.  Other than that the only other native grasses were small amount of Little bluestem, a single (probably common) Dichanthelium sp. and some Tridens flavus- a PA native grass, which I'm not quite convinced occurred in this region historically.

A small colony of Rudbeckia trilobata was starting to bloom at this site.  Somewhat surprisingly this species is absent from big hollow prairies but mixed throughout the prairies in the Bellefonte area.  The Rudbeckia found at big hollow in great numbers is Rudbeckia hirta (see below) a very fuzzy leaved wildflower with a loosly annual to biennual lifecycle.

Rubeckia hirta (mostly left side) 7/8/11, Big Hollow

Next year, look for this in late June: Plantanthera lacera

I took this photo on July 8 when Harry Henderson was showing me some prairie patches east of the main ones at Big Hollow.  Harry had mentioned about seeing this orchid last year at big hollow in a different location.  This is the first time I've seen P. lacera and its a rare form to boot.  This form grows on xeric limestone derived soils, while the more typical form found in PA is a denizen of acid bogs.

A visit to a prairie in Clinton Co.

I had seen this prairie last fall while riding my bike.  I was surprised to find nearly pure stands of indian grass mixed among redcedars.  It was late fall and nearly everything was dormant and dessicated.  So I returned there today to if I could find any rare prairie forbs or even graminiods that might be more visible now that its the field season.  I Checked the soil map for this site and was encouraged by what I found.  It sits atop the opequon series, the prime soil series for XLP flora.  Unfortunatley no rarites were seen.  Forbs were commoners, limited to Solidago juncea, Desmodium candadense, Fragaria virginiana and Rosa carolina.  Below is a typical view of the forb cover for this site.

 Indian grass was dominant, Elymus hystrix, a small statured Dichanthelium and at least one Carex sp. were mixed throughout.  Below is the sedge.

 

The cedars are responsible for casting most of the shade on the prairies grasses at this site.  Exotic shrubs are in the near by woods but not in the extant prairie areas.

There are a few areas like this at the site which will produce a decent amount of indian grass seed, though you can't quite tell yet.

Polygala verticillata

Above is a milkwort that was recently spotted at the big hollow prairie for the first time.  It is a whorled milkwort, Polygala verticillata probably var. isocycla (thanks, Harry).  It grows in single colony on the main prairie at big hollow in a very poor, dry site, which accounts for its especially small size.  It differs from the seneca snakeroot, also a Polygala (sp. senega), most markedly by practicing an annual life cycle and, of course, by its whorled leaves.  Not surprisingly, whorled milkwort's phenology differs from P. senega, blooming June through July and possibly longer (moisture permitting).  Its seeds ripen sequentially, dropping off as they ripen. This makes a one shot harvest and subsequent sowing impossible for the impatient restorationist.

Culver's root: Veronicastrum virginicum

Culvers' root is a native plant that takes some searching to find here in central PA.  Below I have photos of specimens from three locations that I saw recently two of which were in locations I would have assumed to be too xeric to support them. 

 

These first two photos are of the same specimen located near a powerline right-of-way near Coleville.  The habitat is a south facing slope, xeric, thin soil derived from limestone (probably of the opequon series).  The habitat surprisingly does not contain many of the native C4 grasses I thought would grow here, but is heavily studded with eastern red cedars and many common native forbs associated w/ XLP's.  Perhaps this area would be better characterized as a limestone cedar glade/woodland complex.

Next is a specimen I found today at the Big Bluestem Prairie at Big Hollow.  Once again this plant has grown in a drier place than expected, w/in the root zone of Centaurea maculosa, which is a exotic invader, but is nonetheless a pretty good indicator of xeric soil.

Finally there's this markedly taller specimen growing in a solidly mesic location amongst canada goldenrod and wild bergamont at the PSU arboretum woods. 

Asclepias viridiflora sets fruit

Pictured above is a stem of A. viridflora that has decided to set some fruit in spite of the decent July drought.  This year has been the best yet for the green milkweed at the big hollow site and perhaps its deep root system and the abundant june rains will bring about some mature seed.  This may just be the first seed set for this species at this site since I started monitoring it 5 years ago.

Today I also visited the Big Bluestem Prairie at Big Hollow and have found that nearly all the spikelets of Bromus kalmii are mature and ready for collection and/or dispersal.





Moving back to the main Side-oats gramma grassland at big hollow I spotted a flowering Desmodium (probably sp. paniculatum).  I was amazed how this humble legume was flowering in a place where even the prairie grasses had opted to go semi-dormant and crisp.  I've notice in this dry July that the side oats gramma is staying greenest and putting up the most inflorescences in areas that supported exotic shrubs prior to our restoration efforts starting in 2006.