A Walk in Fern Bluff Park
February 10, 2001

Archives of previous walks in the park: 12 May 2007 05 May 2007; 28 April 2007, 21 April 2007, 14 April 2007,  1 April 2007 Easter Egg Hunt; 24 March 2007,  17 March 2007; Nov. 03, 2001; April 04, 2001; March 25, 15, 10-11, 04, 2001; February 2418, 10, 2001

A new soccer field takes shape:

The object of today's walk was to look at the plant life in Fern Bluff Park, but that plan was derailed by the sound of a chain saw. Somebody was cutting down trees on the boundary between Fern Bluff Elementary and the park. Curiosity insisted on an answer, and one was not long in coming. Debbie Montag, shown in the foreground of the right half of this photo, explained that a new soccer field was under construction at Fern Bluff

Fern Bluff Park's Flora is Sparse...

...at this time of the year. But the berries on this Mountain Cedar (Juniperus ashei) were plump and juicy today. Juniper berries are consumed by many species of birds and small mammals, including bobwhite, American robin, Gambel's quail, cedar waxwing, curve-billed thrasher, gray fox, raccoon, and the thirteen-lined ground squirrel. They have a pungent fragrance and taste just like they smell... And the other animals can have them!

Prickly Pears look about the same today as in the summer. The photo is of a spined form of Opuntia lindheimeri. Note the tufts of barbed glochids at the base of each set of spines, both of which are actually modified leaves; the glochids cause more problems than the spines, being hard to extract once stuck in the skin, and tending to burrow deeper the harder one tries to remove them. Moral? Don't touch the glochids... its not worth it. 

Spineless (even tuft-less) forms of this and other species of cacti are also found here. Prickly Pear fruit and joints were used as food by native Indians for centuries, and some folks eat them today. The joints (the fleshy, paddle-shaped parts of this cactus, which form the stem of the plant) are cooked or eaten raw (some stores, including HEB, carry them as the vegetable "Nopalito").  The species name, lindheimeri, honors Ferdinand Lindheimer, a German-born botanist who collected extensively in Texas in 1836 and 1842.

Lichen biology is another fascinating, but neglected, field of science. What we see on the limb of this Cedar Elm tree is a sophisticated symbiont. Elms seem particularly susceptible to hosting both lichens and parasites (most lichens are not actually parasitic), so it was not surprising to find that this same tree was infected with mistletoe to boot. Lichens are complex organisms, involving the mutually beneficial union of a fungus, an alga, and/or a cyanobacterium. The resulting structure is considered rather ugly. Yet, upon close inspection, it has a legitimate claim to "beauty", too. But you have to look for it... 

Today's flower was most likely H. nigricans, judging from its fine, threadlike, lanceolate leaves; H. crassifolia's leaves, especially midstem and higher, are elliptical or oval in shape, although that species can be highly variable, too. Of course, this flower does not care what we call it, or even if we notice it. The tiny petals were designed to attract pollinating insects, who drop by for its nectar and, while partaking thereof, fertilize the flower's ovaries with pollen inadvertently picked up from a neighboring bluet.

And speaking of dropping by, it won't be long before the Purple Martins return to this part of Central Texas. No, this bird's nest is not a Purple Martin's. What would you guess? Sorry, no experts here in ornithology, and recognizing bird's nests is the mark of a truly accomplished "birder". But we have a Purple Martin house in the back yard, and last year it housed 9 pairs and produced about 30 little martins. Whatever birds built this cup nest, the lack of leaves on this tree makes it pretty vulnerable. But fresh, new greenery will be popping out all over in just a few more weeks, and if the same birds return for another season, they should find this location pretty safe for raising another brood.

Elementary and some of the Mountain Cedars were being cleared to make room for it. The chief architect of this project, Debbie said, is Charlene Lehman. Charlene was not present, but her husband, Burt, wielded the chain saw in the left half of the above photo (part of his body is visible in the photo on the left). The plan is to have the field finished by Spring Break. Others were also helping, but this is a major undertaking and they are going to need more help... so if you want to get involved, get in touch with Charlene, Burt or Debbie. Who knows what this soccer field will produce in the soccer hall of fame to come! We are looking forward to watching the first game...

This greenbrier, of the Smilax Family, was among the greenery that could be seen here and there in the park today. Pardon my earlier report, but this may not be the Saw Greenbrier (Smilax bona-nox L.) after all. It does not truly match any of the briars in the references available to me at present (including Robert Vines "Trees, Shrubs and Woody Vines of the Southwest", and the National Audubon Society's "The Pederson Field Guide to Trees & Shrubs"). The leaves are possibly too young to have fully developed all the characteristics of their species. They will be examined more closely in the coming weeks in order to arrive at a firmer conclusion regarding their identity. Smilax bona-nox is well represented in the park, but so are several other species.

Now that the leaves are gone from the Oak trees in the park, the oak galls are much more obvious. These are caused by inquiline wasps. The word inquiline has a Latin origin, and means, roughly, to "live as a tenant." The wasps, in this case, "trick" the Oak tree into building their houses (the galls) for them. The female wasp lays an egg in a tiny hole in the bark of the tree, and a gall (each of the spherical objects in the photo) results. This occurs because the larva of the insect introduces a cecidogen, which is a gall-producing chemical, into the tissues of the plant. This chemical is thought to mimic plant growth hormones, producing cellular hypertrophy, or abnormal, exaggerated growth at that site. Scientists are still debating the exact mechanism involved.

Lichens are not the only things in nature whose beauty is hidden from casual view. Narrowleaf Bluets (Hedyotis nigricans) are often overlooked because of their smallness. This is especially true in February, when their numbers are as diminutive as their tiny flowers. By March they will blanket much of the fields and meadows here. Still, most folks will not see them. This tiny flower is also known by the names diamondflower and fineleaved bluet. The scientific literature on this plant has accumulated as many as 17 different names over the years, all for the same species, which attests to its natural variability. When found deeper in the park (this photo was taken in an open meadow bordering the park and the recreation field) this species tends to stand 12-18 inches tall, displaying its flowers on multi-branched panicles, but here it was, all sprawled out, just like another distinct species, the Small Bluet (H. crassifolia), that is also common in February. 

Thanks for the company... And come along again next week for another walk in the park. Spring flowers are just about to burst into bloom, and with luck we'll capture one or two of them on digital "film"

Archives of previous walks in the park: 12 May 2007 05 May 2007; 28 April 2007, 21 April 2007, 14 April 2007,  1 April 2007 Easter Egg Hunt; 24 March 2007,  17 March 2007; Nov. 03, 2001; April 04, 2001; March 25, 15, 10-11, 04, 2001; February 2418, 10, 2001