Editing Eastern Prickly Pear (section)

== Inconclusive Explorations ==

A major portion of my survey of Connecticut's ''Opuntia humifusa'' involves attempting to locate colonies which were confirmed to have existed historically, but for which there is little or no modern data which confirms or denies their continued existence.  Originally, this area of my research relied primarily upon the mention of ''O. humifusa'' in historic books (that is, books published at least 75 years ago).  However, with the discovery of the George Safford Torrey Virtual Herbarium, my research focus has shifted to those places where botanists have historically collected professionally-verified specimens of ''O. humifusa''.

While herbarium specimens are now the basis of my research and explorations, I have kept other historic references to certain colonies in the overviews below.

=== Naugatuck State Forest (Beacon Hill Area) ===

The presence of ''Opuntia humifusa'' in Beacon Falls, Connecticut is only known through historic records.  This includes two herbarium specimens (one of which was collected in 1892 and the other collected most likely between 1900 and 1910), one brief reference in a book published in 1896 and one brief reference in a book published in 1910.  From 1911 and onward, it would seem that no further mention of this colony has been made in any published literature, scientific or otherwise.  Thus, it is difficult to say with any certainty whether or not this colony still exists.

==== Historic Information ==== 

The earliest, and the most reliable, record of ''Opuntia humifusa'' living in Beacon Falls, Connecticut comes from the George Safford Torrey Herbarium at UConn which contains a specimen of ''Opuntia humifusa'' collected by E. H. Eames on July 6, 1892.<ref name="gst-herbarium">''The George Safford Torrey Herbarium''. Department of Ecology and Evolutionary Biology, University of Connecticut, n.d. Web. 4 May 2012. <http://bgbaseserver.eeb.uconn.edu/database.html>.</ref>  The collection location is listed simply as "Beacon Falls".  Of note, the herbarium specimen includes a flower bud, indicating that the plant collected by Eames was at least healthy enough to produce flowers.

The next reference to ''O. humifusa'' in Beacon Falls appears in [[The Town and City of Waterbury, Connecticut, Volume 1]], published in 1896 by Sarah Johnson Prichard, which mentions that "the prickly pear is common on the summit of Beacon Hill, just south of the line of ancient Waterbury".<ref name="waterbury">Prichard, Sarah Johnson. ''The Town and City of Waterbury, Connecticut''. 1. Waterbury: The Price & Lee Company, 1896. 11. Print. <http://books.google.com/books?id=U_QLAAAAYAAJ&printsec=frontcover></ref>

Another specimen of ''O. humifusa'' can be found in the Yale University Herbarium (YPM CBS 016314)<ref name="yuh">"YPM Botany - Online Catalog." ''Yale Peabody Museum of Natural History''. Peabody Museum of Natural History, Yale University, n.d. Web. 16 May 2012. <http://peabody.yale.edu/collections/botany>.</ref>.  There is no collection date associated with the herbarium record.  However, the collector of this specimen, H. S. Clark, was also the collector of specimens from other towns that date to 1903 and 1906.  Thus, it is likely that the collection date of this specimen is in the same general timeframe between 1900 and 1910.

The latest reference to ''O. humifusa'' living in Beacon Falls occurs in a 1910 publication, "[[Catalogue of the Flowering Plants and Ferns of Connecticut Growing Without Cultivation]]", authored by Charles Burr Graves.  Graves briefly mentions that ''O. humifusa'' can be found in "Naugatuck and Beacon Falls".<ref name="catalogue-1910">Graves, Charles Burr. Catalogue of the Flowering Plants and Ferns of Connecticut Growing Without Cultivation. 14. State Geological and Natural History Survey, 1910. eBook. <http://books.google.com/books?id=SSQwAAAAYAAJ&printsec=frontcover#v=onepage&q=opuntia&f=false>.</ref>  Graves attributes this assertion to J. K. Goodrich, though I have been unable to find any published material by Goodrich which might provide further information.

==== Preliminary Assessment ====

Examination of satellite imagery of Beacon Hill area reveals several promising locations for the presence of ''O. humifusa''.  The area of Beacon Hill is now contained within the Naugatuck State Forest.  Entrance to the state forest is via a blue-blazed trail.  However, the trail itself does not pass through the promising habitat areas.  If unmarked side trails aren't present from the blue-blazed trail, then considerable bush-whacking will be required to explore the potential habitat areas.

==== Exploration ====

===== April 19, 2012 =====

On April 19, 2012, I conducted an on-site exploration during which I thoroughly inspected roughly 30% of the possible habitat areas that I originally identified on Beacon Hill through examination of satellite imagery.

The promising areas that I explored are essentially high-elevation clearings on the southwestern slopes of Beacon Hill where the bedrock is exceptionally close to the surface.  Tree growth was minimal on these patches due to a lack of soil and, perhaps, harsh environmental conditions.  This presented at least two promising factors for the existence of ''O. humifusa''.  First of all, the elevation of these areas means that they are, more than likely, slightly warmer than the surrounding valleys (where colder air is apt to pool).  Second, the openness of the clearings offers considerable exposure to sunlight.

===== May 5, 2012 =====

A second exploration was conducted of promising areas further west-southwest of the original exploration area.  Another 30% to 40% of the potential habitat locations was investigated, most of which was essentially similar to the habitat discovered during my first exploration.  Again, no evidence of 'O. humifusa' presence could be located.

==== Status ====

I have not explored all of the possible locations on Beacon Hill where ''O. humifusa'' may currently live.  However, I ''have'' thoroughly examined a very large percentage of those areas (at least 60% to 70%).  Because the remaining unexplored locations are in close proximity to the areas that I have already explored, and because the the unexplored areas most likely share similar or nearly identical habitat conditions, I am skeptical that ''O. humifusa'' still lives on Beacon Hill.
 
Until I explore every individual ledge on Beacon Hill, however, I will not be able to say for certain that ''O. humifusa'' is extinct on that mountain.  My examination of confirmed colonies of ''O. humifusa'' in both Plainville and New Haven has revealed that the plant may flourish in extremely isolated areas despite being in very close proximity to relatively large areas of similar habitat.  Therefore, it is entirely possible that one of the few ledges on Beacon Hill which I did not investigate may contain a colony of ''O. humifusa'' which, for one reason or another, has been unable expand its range to similar habitats on nearby ledges.

==== Exploration Location ====

This exploration involved an improvised loop hike of approximately 2.88 miles throughout the Naugatuck State Forest in the area of Beacon Hill in Beacon Falls, Connecticut.  Please note that the habitat area which I explored was ''not'' found along the widely-used blue-blazed trail.  Reaching the exploration area on the southwestern slope of Beacon Hill required considerable hiking on trails which aren't seen in the CFPA map of Naugatuck State Forest.  Bush-whacking was also necessitated in some instances.

<ul>
<li>To download the GPS tracklog of this exploration (KML  format), [[Media:Naugatuck-State-Forest-Beacon-Hill-Area-(Prickly-Pear-Cactus).kml|click here]].</li>
</ul>

==== Possible Explanations for Absence ====

Given that the presence of ''Opuntia humifusa'' in Beacon Falls between the 1890s and early 1900s is confirmed, there are two distinct possibilities that might explain my inability to locate any of the cacti in modern times.

===== Imprecise Historical Literature =====

For one, the herbarium specimens of ''O. humifusa'' are the primary pieces of evidence confirming their presence in Beacon Falls.  However, neither of these herbarium records actually state that the plants were found on Beacon Hill; they simply relate the collection location as "Beacon Falls".  Hypothetically, this could mean that the herbarium specimens were harvested anywhere within the boundaries of Beacon Falls.

The single piece of historical literature which actually pinpointed the location of ''O. humifusa'' on Beacon Hill was Prichard's book on the history of nearby Waterbury.  While Prichard may have been fairly knowledgeable on the topic of Waterbury, there is no evidence that she possessed the same depth of knowledge concerning neighboring Beacon Falls.  It may well be that when Prichard wrote that "the prickly pear is common on the summit of Beacon Hill, just south of the line of ancient Waterbury", she was simply using Beacon Hill as a general landmark with which most people of that day would be familiar.  It could well have been that the cacti never actually existed on Beacon Hill, but instead existed on some unnamed hill within the same general region.  Prichard would simply have referred to it as "Beacon Hill" for lack of a better-known landmark.  In that case, it is possible that the cacti could instead exist on or around the bald cliffs to the west (on the opposite side of Route 8).  I have yet to investigate this alternate location, but will do so as time permits.

===== Local Extirpation =====

Perhaps a more likely scenario is that ''O. humifusa'' did in fact exist on Beacon Hill between 1890 and 1910, and that it may have continued to flourish for some decades afterwards.  We can assume that Beacon Hill probably would have been sparsely wooded around the turn of the 20th-century, perhaps even largely devoid of trees.  The area of Beacon Hill may well have been cleared to some degree to make room for pasture land and, to a lesser degree, for lumber.  The lack of competition from trees on Beacon Hill would've meant that cacti could take advantage of full sun on the well-drained soil upon the mountain.

However, as the case has been with most old pasture land in Connecticut, the use of Beacon Hill as a grazing area would have expired no later than the very early 1900s, perhaps earlier.  In the time that followed, trees would have been able to begin taking root and growing, eventually culminating in the mature forest and solid woodland canopy that covers the mountain today.  If this scenario is correct, and it seems that it is, this would mean that the cacti documented on Beacon Hill in the 1890s and early 1900s would have ultimately been doomed.  With each passing decade, the tree cover would've expanded and thickened.  In time, any colonies of ''O. humifusa'' living upon the mountain would literally have been shaded out.  Perhaps they could've persisted in the light shade of younger trees for a decade or two, but as the canopy grew more dense, cutting off light to the ground, the cacti would've first lost their ability to flower, and then lost their ability to gather enough sunlight nourish themselves.  At that point, the cacti would've perished fairly quickly, leaving behind no evidence of their presence.

Although this scenario comports quite closely with the known agricultural and ecological history of the Connecticut landscape, what evidence is there that conclusively suggests this pattern of local extirpation actually occurred?

For one thing, aerial photography from the early 1930s reveals that the forest upon Beacon Hill was still somewhat sparse by comparison to the modern forest we see today.  In fact, there were still some cleared parcels of land upon the hill which appear to have been farms of some kind (perhaps tree farms).  Thus, we know that only sparse forest existed on Beacon Hill some 20 to 30 years after ''O. humifusa'' was documented there.  The presence of sparse forest could hypothetically be explained in various ways.  For example, it could have been that the forest was thinned for lumber in the late 1920s.  Perhaps a forest fire tore through the forest in the 1910s, leaving only select fire-hardy trees.  Although these possibilities cannot be ruled out, they aren't especially likely.  In the 1920s, it is more probable that a lumbering venture would've simply clear-cut the entire area rather than merely thinning the forest.  The notion that a forest fire thinned the forest is perhaps plausible, but I cannot find any historical evidence of such an extensive forest fire in that area.  It is most probable that the sparse forest was actually just immature forest; the result of young "pioneer" trees growing upon land that had been entirely clear of significant tree growth at least one or two decades earlier.