Sunset at Big Hollow Main Prairie

The Xeric Limeston Prairie Garden

XLP garden plot

This year has been the first growing season for three garden beds planted with locally collected prairie seeds.  The process of preparing these gardens started last growing season with the spraying of the garden beds.  I sprayed the beds with 3% glyphosate solution several times throughout the growing season in order to kill persistant perrenials and to start to deplete the seed bank of various annual species.  This practice of spraying throughout the season takes patience and persistance, but having a seedbed free of competing vegetation makes establishing a garden from seed very simple.

All three of these beds contain a similar mix of species.  The grass component of the seed mix includes (listed in order of abundance), sideoats grama, little bluestem, poverty oatgrass and arctic brome.

Chinese mantis: Tenodera sinensis

 The forb component was planted separately in early February to allow time for the forb seed to stratify.  Most forb species seed will not germination without exposure to a cold moist enviroment over a period of about two months.  The february sowing seemed to be adequate for breaking seed domancy of most the species planted which includes, Rudbeckia hirta, Eupatorium altissimum, Asclepias tuberosa, Asclepias verticilliata, Asclepias viridiflora, Solidago juncea, Solidago nemoralis, Allium cernuum, Trichostema brachiatum, Heliopsis helianthanoides, Pycnanthemum incanum, Blephilia ciliata, Desmodium paniculatum and Aster laevis.  At the time of sowing the seeds were simply scattered evenly of over the soil surface, and were buried over time by the heave/thaw action of the winter time soil.

maryland senna: Senna marilandica

Pictured above is my maryland senna seed production patch I planted in spring of 2011.  To prepare them for germination I pulsed the extremely hard seeds in a blender to chip and scarify the seed coat.  Senna seeds will not germinate without mechanical scarification or weathering in the soil over a period of a couple years, so I choose the short term option.  These plants originated from seed collected from several small plants growing in a Juniata County XLP under very dry rocky soil conditions.   Growing them out in this double dug vegetable garden allowed these plants to reach their current size and produce a similar amount of seed in their first year of growth from seed.

sideoats grama: Bouteloua curtipendula

This is my sideoats grama seed production bed.  It was established from seed from several prairies in Centre County in 2012.  This plot is also located in a old vegetable garden bed and the grasses have managed to bloom and set quite a bit of seed in their first season of growth.  The red colored parts of this plant are the pollen producing anthers.

This garden was previously planted in virginia wildrye along with some other flowers. In midsummer before the wildrye set seed I applied gylphosate throughout the bed.  Since the initial application I made several isolated follow up treatments. I decided to the leave the exotic Buddleia or Butterfly bush as it smells so nice and pollinators love it.  It does have the ability to self sow, but not to an unmanagable degree.  Beside the Buddleia, I left three eastern redcedars in the bed to provide some evergreen cover and to create some of the physical structure of the local prairies.  This plot gets more shade from the nearby walnut canopy and will probably have no true prairie grasses seeded.  Im considering using bottle brush (Eylmus hystrix) as the dominant graminoid in the background areas of this plot, with the shorter poverty oatgrass (Danothonia spicata) planted in drifts in the foreground area.

Slender lady's tresses: Spiranthes lacera var. gracilis

The slender lady's tresses started blooming about a week ago at the Main Prairie. These flowers are fairly abundant this year.  I would estimate a total of 20 to 30 flowering stems are blooming throughout the Main Prairie.

Before today I have never seen butterflies utilizing spiranthes for nectar.  Pictured above is a pearl crescent butterfly.  In this same area I spotted 2 small hairsteak butterflies which were also actively feeding on this orchids flowers.

Stiff goldenrod: Solidago rigida

The stiff goldenrod and gray goldenrod populations at the Main Prairie are responsible for the prairies current color scheme.

Back to the Main Prairie

The Main Prairie at Big Hollow

 

Compared to mid July the Main Prairie has entered a lull period in its flower phenology.  The slight haze of yellow in places foreshadow the flowering of several species of goldenrod later in August.

and has

Cirsium discolor patch

 

 

In areas along the woods edge field thistle has started blooming. These areas have become a fixture for nectar foraging insects.

Hemaris thysbe: Hummingbird Clearwing

Big Hollow Mesic Prairie

Northern blazing-star: Liatris scariosa

The Liatris scariosa plants at the Mesic Priairie at Big Hollow are blooming presently. 

Heliathus strumosus

Pictured above is a large colony of sunflowers that grow out onto the footprint of a sewer line right of way.  This area looked more less like bare mineral soil last winter from heavy equipment activity.  Fortunately the disturbance in this area was very superficial and the prairie and this adjacent sunflower patch were not damaged.

The Sporobolus Grassland

Today I visited a unique grassland not far from the Big Hollow Prairie.  I've come to call it the Sporobolus Grassland, be cause poverty dropseed or Sporobolus vaginiflorus is the dominant graminoid at this site. 

Allium cernuum was blooming in abundance

 Poverty dropseed leaves are long and wiry and create a beautiful wispy texture in grasslands where it predominates.  Unfortunately this seems to be last remaining dropseed grassland in the area.  Most grasslands in Pennsylvania are not stable and are changing to woodland and invasive shrub thickets.  Black walnuts are encroaching upon this grassland.  In addition, the exotic invasive bush honeysuckles and autumn olive are problematic invaders at this site as well.

Flowering spurge: Euphorbia corrollata

Flowering spurge is blooming in abundance in this habitat.

A small colony of Pale indian plantain: Cacalia atriplicifolia, grows at this site

Siphium trifoliatum

Above is a photo of Silphium trifoliatum at the main prairie.  The main prairie contains many of these plants but most years only a few of them will bloom.  This year I have counted 15 blooming plants at Big Hollow's Main Prairie. Deer herbivory on this Silphium population has always been voracious, but this year the deer seem to have held back a bit.  I will guess that this can be attributed to two changes from the previous seasons.  Wetter weather (up until July) has increase plant biomass, but also clearing the woodlands surrounding the prairies of exotic shrubs and vines has removed a lot the cover the deer need to feel secure in the area.  Clearing the surrounding woods has been a win-win situation for the Silphiums at Big Hollow, reducing deer herbivory and releasing many established plants from deep shade.

July 18,2012

Variegated Fritillary (Euptoieta claudia)

Harry Henderson sent this great picture of a variegated fritillary at Big Hollow.  He explained that the variegated's are fairly uncommon for the area and are not seen every year.  Also this species is not a resident, as it invades northward from its permanant range in the south each summer.

Cirsium pumilum

I'm glad to report that the Cirsium pumilum population at big hollow is expanding.  This year has produced more flowering plants since the restoration began.  Presently it is range is limited to two smaller disjunct prairies within the Big Hollow restoration area.  If things continue to go well for these thistles this year I should be able to collect a good bit of seed to spread around the main prairie at big hollow.  Pollinators should greatly benefit from this population expansion of this native thistle as it has an earlier phenology than the already well establish native Cirsium discolor.  

A veiw of the upper section of the Main Prairie from the woods.

A view of the lower end of the main prairie.

The main prairie at big hollow appears to be more flowers than grass at this point in the season.  Part of the reason for this abundance of blooms is that that flowering forbs have colonized most of the cleared and restored areas faster than the prairie grasses.  In the above photo, the left half of the frame contains a stable grassland that was present before I started the restoration project.  The right half of the frame was mostly covered by autumn olive canopy four years ago.  This side does indeed contain all the grasses found on the left although at a reduced density.  I think that as time goes on the right side will become grassier.  But for time being I will enjoy this garish display.

The growing season so far has been favorable for plant growth at Big Hollow.  Things are starting to get a bit dry now but June and May brought a good bit of moisture to the hollow, resulting in taller plants and in some cases more profuse flowering.  A visit to Big Hollow today revealed many of the prairie's showiest flowering plants at or close to their peak floral phenology.

Monarda fistulosa

Asclepias viridiflora

Some of the green milkweeds at big hollow have been blooming for a couple of weeks now.  There is an abundance of blooming green milkweed this year making me hopeful for a large seed crop.

Solanum carolinese

 The heavily rhizomatous horse nettle has beening spreading through a section of the main prairie and has been blooming for weeks now as well.

Scutellaria incana

The Hoary skullcap has just recently started blooming here. In fact, this individual appears to be the first in bloom.  The plants closer to the woodland edges have yet to reveal their purple-blue flowers.

Asclepias purpurascens

 

I was delighted to find a single flowering purple milkweed stem at the mesic prairie at Big Hollow recently.  Purple milkweed is uncommon throughout much of its range, including here in Pennsylvania.  

Unfortunately I don't think this plant will produce seed without another individual to exchange pollen with.  Hopefully there are other purple milkweed plants in the area, still gaining size and vigor, which will bloom next year.

Local Cedar Glade

Today I visited a local cedar glade for the first time.  I was expecting to find many of the important prairie grasses and associated forbs at this site since it appeared to be in an ideal location, surrounded by forest on a difficult to access slope.  I assumed that such isolation would would ensure unsual or rare native plants would abound.   Unfortunately this was not the case.  The glade habitat appeared depauperate from past land use.  The glade was surrounded by barbed wire and had been used as pasture many decades ago.  Exotic grasses such as, timothy, canada bluegrass, kentukey bluegrass, Bromus tectorum and orchard grass have invaded and persisted since this area was pastured.  Simalarly exotic forbs like oxeye daisy, viper's bugloss, spotted knapweed were detected.

Poverty oatgrass, a native grass was by far the most abundant graminoid.  Dichanthlium acuminatum, D. linearifolium, Andropogon virginicus and Tridens flavus were also present. 

These pleasant woodlands developed atop the slope.  The grass cover here is a mixture of virginia wildrye, orchardgrass and bottlebrush (listed in decreasing abundance).  Tree species included black walnut, eastern redcedar and honey locust.

In areas of sparse vegetation reindeer moss (Cladonia sp.) thrives.  The blue flowered plant is viper's bugloss (Echium vulgare) a exotic weed that seems particularly suited to these dry, sunny, limestone sites.

Monarda fistulosa was the most abundant native forb at this site.  None of these plants seemed to exhibit the densely hairy leaves and petioles found on the big hollow plants.

A XLP along Spring Creek

This high quality priairie remnant has persisted on a small powerline right of way.  The site is small in size covering approximently 5000 square feet.  While casual botanical surveys of the site have yet to reveal any state listed species, the site is remarkabley free of troublesome exotic herbaceous plants like spotted knapweed, ox eye daisey, sweet clovers and crown vetch which plague that majority of the states limestone prairie remnants.  Even the the woody plant species invading the grassland is composed mostly of native plants, such as, Yellow oak, fragrant sumac, black walnut, ash and ironwood (dominant).  The problematic Morrow's and Amur honeysuckles are present at this site as well as autumn olive albeit in small amonts.

Below is a list of some of the native species observed at this site.

Graminoids:
Sorgastrum nutans
Andropogon gerardii
Schizachyrium scoparium
Bouteloua curtipendula
Danthonia spicata
Carex spp.

Forbs:
Hepatica sp.
Blephilia ciliata
Zizia aptera
Pycnanthemum incanum
Calystegia spithamaea
Monarda fistulosa var. mollis
Monarda clinopodia
Mianthemum racemosum
Uvularia spp.
Helianthus spp.
Lespedeza spp.
Solidago juncea
Solidago nemoralis
 Allium cernuum

Woody plants (within grassland area):
Quercus muhlenbergii
Quercus alba
Fraxinus sp.
Rhus aromatica
Ostrya virginiana
Juniperus virginiana
Ceanothus americana
Tilia americana

Plus many other species.  I hope to eventually get the time to completely survey the grassland.

A recent visit revealed many Rosa carolina plants in bloom

Another large flowered plant currently in bloom is Calystegia spithamaea

Blephilia ciliata

A view from the downhill end of the grassland

Big Hollow Herps

This is the first time I've seen a black rat snake this year and it was a big one.  I only got to look at it for a few seconds as I unitentially spooked it, but it was probably close to five feet long.
It may be that the big hollow prairies are becoming more comfortable for local reptiles as more brush is cleared and more sun is reaching the ground.

 
The snake was able to quickly disappear into the pile of rocks.

Garter snakes seem to be a nearly constant presence around big hollow as well.

Young Cedars and Winter Maintainence

 

Red cedar seedlings are becoming conspicuous in this area of the prairie.  At this point I'm content to let some these trees grow a while.  Red cedars are not the greatest threat to the prairies in these areas, and since they don't resprout from cut stumps they are easy to control.

Seedlings of red cedars have needle like leaves.  The leaf scales develop later on in the plants life cycle.

Juniperus virginiana seedling

Above is an autumn olive sprout that is reestablishing dominance.  A 15% solution of triclopyr in a oil carrier, applied with a sponge on a stick will take care of these sprouts neatly.

These native black raspberries severely impact the quality of the prairie plant growth.  I plan on targeting these with triclopyr on a stick as well.

So far the winter has been mild and nearly snow-free allowing for many productive days of cutting and treating.  This winter's goal of cutting and treating all of the big hollow restoration area is well with in reach.