TLR ecology revised web by HC121107201947


									                 THE ECOLOGY OF TIERRA LINDA:
            “In the end we will conserve only what we love, we will love only what we understand,
                                and we will understand only what we are taught”
                                                                               -Bada Dioum

                                           Jim Stanley
                                            April 2002
                                      Revised, January, 2004


As a chemist by education and profession, I don’t have any formal training in Hill
Country ecology. None of the information contained in this document is original with
me, but rather represents the consensus opinion of numerous experts I have heard
speak, talked to, or read in the past few years. I have attended nearly 300 hours of
seminars, lectures, short courses, symposia, field days, etc, on just about every aspect
of the flora and fauna of the Hill Country. Most of the speakers at these events have
been faculty members from Texas A & M or other universities, folks from the Ag
Extension Service, the Texas Parks and Wildlife Dept, the Texas Forest Service, the
USDA/NRCS, and similar organizations, and in addition, sometimes successful
practicing ranchers. I have attended 5 all day workshops at Bamberger Ranch,
numerous field days at various ranches in several Hill Country counties, and the Kerr
Wildlife Management Area several times. I have taken the courses and completed the
volunteer work to become a certified Texas Master Naturalist. I certainly do not claim
that these studies make me an expert in the many fields of ecology. However, I believe
I do have a fairly good grasp of the basic principles of Hill Country ecology and a
fundamental knowledge of most of the issues of range and wildlife management.

        I have been struck by the unanimity of opinion of experts with different
backgrounds and experience as to what constitutes good and bad land use practices,
and it is these ideas that I hope to summarize here for Tierra Linda residents. It is my
hope that these ideas will help stimulate thought and discussion and perhaps lead to
wiser land use practices by all of us.

      I have to apologize in advance for the length of this document; it is not a simple
subject. My hope is that everyone who lives in Tierra Linda will think it is worth 30
minutes of their time to better understand the ranch ecology and what they can do to
improve it.

How We Got Where We Are

       In the Beginning..........Well, a long time ago anyway, before the Europeans
arrived, TLR would have looked very different. There would have been many fewer
trees of any kind, but a greater variety than there are now, and most of the trees would
have been concentrated near the creeks and springs. Most of the area was a grassland
and the grass was in places 3 to 5 feet tall. Buffalo roamed from here to Canada,
always on the move and never staying in any one place for very long. There were very
few deer, but there were a lot more ground-nesting birds (quail, turkey, prairie chicken)
and a lot of other critters. There were, of course, no starlings, no English sparrows, no
fire ants, no nutria, no blackbucks, no Bermuda grass, no KR bluestem, no Chinaberry
trees, etc. Because of the vast stretches of unbroken grassland, grass fires set by
lightning or by the Indians occurred with some regularity.

       Then the Europeans came. They killed almost all of the buffalo and most of the
Indians. They fenced off the land into individual ranches, and they brought in livestock;
sheep, goats, cattle and horses. Now the livestock were confined within each ranch
and grazed on that same land year round, and because the more animals a rancher
could raise, the more money he made, too many livestock were kept on all of the
ranches and the land became overgrazed. When the grass was eaten down, exposing
the soil to more sun, the seeds of bushes and trees could sprout. The ranchers did
everything they could to suppress and fight fires, and there still were not many deer
around; both of these factors helped the tree sprouts to survive to maturity, so
eventually the Hill Country was covered with trees and bushes. But then the ranchers
(and the US government) began a campaign to eliminate (not just reduce) all predators,
and as they did so, the deer began to increase, and to move into areas that had
previously been grasslands (poor deer habitat) but now had trees and bushes (good
deer habitat). As time went on, overgrazing continued, deer populations increased, and
as a result, many of the bushes and low tree branches were eaten away.

        Given the choice, deer would prefer to eat forbs (weeds and wildflowers) and
browse (leaves of bushes and trees). They will eat only small amounts of grass, and
then only when it is tender and green (it has to do with the nature of their rumen).
Unfortunately, they really don’t like cedar. In fact, nothing does. Goats will eat small
amounts of young cedar, but only when they have eaten most everything else. So as
the livestock began to run out of grass, and the deer populations began to increase,
they started to eat all of the small bushes and low lying tree limbs, but left the cedar
alone. Birds and other animals eat cedar berries and scatter the seeds in their
droppings, so cedar can become widely dispersed quickly. Unfortunately, the climate
and soil conditions of the Hill Country favor cedar growth, so with nothing to check its
growth, we have the dense cedar brakes we see today.

       Finally, as the cedar has grown larger and more numerous, it has taken over
much of the land that used to be in grass, both because the cedar blocks the sunshine
from reaching the grass, and because it also traps a lot of rainfall (60-80% is a
frequently quoted amount of rain that never hits the ground under a large cedar). In
addition, because birds that have just eaten cedar berries like to sit in trees, we
frequently find oaks that are surrounded by especially heavy cedar growth, so the cedar
robs the oaks of moisture as well, contributing to oak decline, and to the decline in the
subsurface water table resulting in a reduction in the number of springs.

       So we have turned the ecology upside down. In the beginning, tall grass and fire
prevented cedar from encroaching on the prairie, and now the cedar has become
dominant and choked out the prairie. Deer used to be scarce and limited mostly to
brushy areas along creeks and the mountains, and predators were relatively plentiful.
Now deer are overpopulated, having expanded into what was once grassland and the
only deer predators are two legged or on four wheels. The deer have gained cover in
the cedar that has converted an open grassland (poor deer habitat) into good deer
habitat, but the cedar provides no food and the deer and livestock have now eaten
everything else that was food.

       TLR is now almost totally devoid of any woody species growing less than 4’ off
the ground, other than cedar, and there are very few weeds and wildflowers (deer don’t
eat Mexican hat, mealy blue sage, prairie verbena or a few other things). There are no
replacement trees for the mature oaks except for the very very few that residents have
planted. This current plant succession, if we don’t do something about it, will lead to
reduced numbers of oaks, increased cedar coverage and poorer wildlife habitat. The
deer population in TLR is 8 to 10 times what is considered ideal for a healthy habitat,
and is sustained at that level partially by supplemental feeding by residents.

Where We Are

       In spite of the undeniable beauty of Tierra Linda, biologically, it is far from ideal.
We have way too much cedar and far too many deer to have the kind of plant
biodiversity that is required for a good habitat for wildlife or livestock. We have cedar
where we should have grass; we have cedar where we should have other bushes; we
have nothing where we should have bushes, weeds, wildflowers, and low tree limbs
(below the 4-5’ browse line), we have relatively unpalatable grass where we should
have little bluestem and grama grasses, and in places we have badly eroded hillsides
almost devoid of soil or anything growing at all.

      Of course we love it here and most of us never think of it in such a critical way,
and that’s good. For most of us it is the only way we have ever seen Tierra Linda; it’s
the way we fell in love with it, and it’s the way the whole Hill Country looks. What we
need to do is first to recognize the situation and then educate ourselves about what can
be done to improve our little piece of heaven.

Guiding Philosophy

         Everyone will have their own views on the environment and how to interact with
it, but so it is clear where the author is coming from, here is mine: I start with the belief
that all living things are precious, and that in matters of the environment, we should
above all do no harm. Furthermore, we should live in such a way so as to leave as small
a footprint on the land as possible, to use as few resources as possible, and to interfere
with all other beings as little as possible.

The Ideal

       It is sometimes useful in deciding what actions to take to first decide on what the
most desired final outcome would look like, and then judge all proposed actions in terms
of what will move you toward that goal. We could set as our goal to return Tierra Linda
to the way it was before the Europeans arrived, but that is certainly unrealistic and
probably impossible. A more realistic, but still difficult goal, would be to transform Tierra
Linda into a ranch similar to the best model ranches in the area today. Two of the
ranches that I am familiar with that fit that description and are open to the public, are the
Kerr Wildlife Management Area and the Selah Bamberger Ranch, so I will describe
what those ranches are like as the ideal, and then discuss what actions we can take to
move us in that direction.

       Stepping out of the car and walking into the pasture of either of the above
ranches, one is first struck by the presence of many small bushes (redbud, sumac,
possumhaw, yaupon, Carolina buckthorn, greenbrier, Texas persimmon, white
honeysuckle, etc., etc.). The next thing one might notice is a much greater number and
variety of weeds and wildflowers growing amid the very substantial grass cover, and the
great variety of grasses. Cedar is also evident, but in most areas it has been reduced to
individual trees that have been pruned up, or areas of cedar left for either wildlife cover
or on hillsides to control erosion. Gazing around the range at deer-eye level will reveal
a number of tree limbs hanging low with leaves still attached. In places where erosion
might be a problem, windrows of cut cedar limbs have been placed across the slope
where they gather leaves and soil, and grass has begun to sprout up between the dead

       How have those ranches attained such a state, when they started out looking
pretty much like Tierra Linda and most of the Hill Country does now? They did three
things: (1) thorough, but selective, cedar cutting, (2) deer population control, and (3)
multipasture livestock rotation giving long rest periods to each pasture. The Bamberger
Ranch transformation is rather famous. When they bought the ranch 33 years ago
there was no surface water anywhere on the 5000 acres. They now have several year-
round flowing springs, a large lake, numerous ponds, and not a single well is needed on
the ranch. In the beginning, it took 41 acres to support a cow/calf pair, now it takes only
18 acres. When they started, the Audubon Society inventoried the ranch and found 48
bird species; that number is now 160.

Many of the things done on those ranches to accomplish those transformations would
be more difficult on Tierra Linda, some might be easier. We can do a lot of the things
they have done, even if on a smaller scale. What follows is a discussion of a number of
things that we can do to move the Tierra Linda ranchland in the “direction of goodness”.


       There is nothing wrong with having cedar (actually Ashe juniper) on your land. It
is natural, native, xeric, and perfectly adapted to the Hill Country soil and climate. The

problem is overpopulation. The solution, therefore, is not to eliminate all cedar, but to
control the amount of cedar and where it grows. One thing to note is that man is the
only effective control of cedar growth in the Hill Country. Plant succession is in the
direction of greater amounts of cedar and more of the other trees and bushes being
crowded out as time goes on. The Kerr Wildlife Management Area has a plot that
proves that if left totally alone for a few decades, all of our land would become a cedar
brake with no other plants of significance.

       It is widely believed (and there is some fairly sound data to support it), that cedar
intercepts a large fraction of the rainfall that falls on it so that the rain never gets to the
ground, the plants near it never get “their share” of the moisture, and the aquifers don’t
get recharged. (The removal of cedar from the Bamberger Ranch, resulting in recharge
of the aquifers, is what is responsible for the springs on the ranch now.) In addition, the
dense canopy of large cedars shades the ground around them, and this, combined with
the needle mulch under the cedars, prevents the growth of grasses or forbs around
them. So cedar is undesirable for three reasons: (1) it soaks up rainfall, (2) it crowds
out other plants, and (3) it occupies land that could otherwise be productive rangeland.
Cedar close to your house, especially if not trimmed up to above 4’, is also a serious fire

        So does cedar have any redeeming virtues? Yes. It provides shelter and cover
for wildlife, and if it is the only thing growing on a rocky slope, it provides some (but less
than ideal) erosion control. The shelter and cover aspect is especially important on
Tierra Linda since we have so little other vegetation to serve that function (agarita and
prickly pear do serve some species).

        How much cedar coverage should we have to provide cover for wildlife? Most
experts say between 5 and 10%.

        So, do we call in the bulldozers and level the cedar? Absolutely not! Bulldozers
clearing cedar can do more damage to the ranch than the cedar ever can. If you are
not going to do a major land restoration immediately after the cedar clearing, and that is
VERY difficult to do, then it is better to leave the cedar, because the one thing that is
worse than cedar is a rocky, bare hillside with nothing growing on it and what little soil
there is eroding away. Once the soil is gone, there is NOTHING that can be done about
it in our lifetimes.

        The soil in the Hill Country is very thin and fragile. Bulldozer or other heavy
machinery tracks disturb the surface, killing fragile grass and inviting the growth of
undesirable plants such as thistles, horehound, buffalo burr, and others in addition to
inviting erosion.

        Cedar clearing is best done gradually over a period of years. If at all possible, it
should be done by hand (chainsaw). In a solid cedar brake, plan on removing less than
half of the trees the first year; removing one third or one fourth is better. And select the
trees for removal in a random pattern, not all in a row. Then lay a thin layer of the cut

branches on the ground where the tree was removed to hold in place the leaf litter and
oak leaves that were under the cedar. The limbs will also protect any grass shoots from
being eaten by deer or cattle until the grass is well enough established to survive
grazing. If removing cedar from around an oak, it is also a good idea to not remove all
of the cedar the first year, but to take a third or less each year. Also, the very large old
growth cedar, frequently single trunk trees, can make very attractive trees when
trimmed up.

       If hand clearing is absolutely not possible, then a Bobcat with cedar snippers is
not too damaging. A third method, called a Hydro Ax is a larger machine that grinds the
cedar bushes into a coarse mulch which is spread around the area. This eliminates the
necessity of having to haul off the branches or burning, which has its own problems.

        What should you do with the cut cedar? By far the best thing to do is to have it
chipped so the chips can be used either around your garden as mulch or spread thinly
over any bare ground. This not only keeps the ground cooler and reduces moisture loss
but also adds much needed carbon and other nutrients back to the soil. If chipping is
out of the question, then hauling to the cedar dump is preferable to burning because it
doesn’t leave a burn scar on your lot, and it is safer for everyone. If burning is your only
option, then please obey the burn regulations, start any fire early and small and feed it
continuously rather than make a huge pile and torch it at once. Have water handy if at
all possible and stop burning early in the afternoon so the fire can die and/or be put out
before dark.

       Just cutting the cedar is not helping the land much if grass doesn’t grow back
where the cedar was, and cutting the cedar and allowing the soil under it to erode away
is making matters WORSE. Getting grass to grow back is difficult. If we had fewer deer
and could exclude the cattle and black buck for a year or more, then the grass would
have a much better chance, but since that is not the case, the grass has to be protected
by a thin layer of cedar limbs. Also, if the cedar is cut from an area with any significant
slope, then making a small windrow of cedar branches across the slope to prevent
erosion would be very helpful. If a third of the cedar is removed the first year, then in 3
to 5 years all of the original cedar will have been cleared, except for some areas that
you purposely leave for wildlife habitat, privacy, and/or to protect a slope. For an 8 acre
lot, 5% remaining cedar is an area about 45 yards square, but that could also be two or
three smaller areas.

       So, now that we have cut all the cedar we think we need to, we are finished,
right? Unfortunately, cedar management is an unending, ongoing activity, due to all of
the small cedars that are sprouting from seeds birds have dropped all over your
property. So, on pretty spring days or bright fall days, you will have to take a stroll with
your spouse and your loppers and cut the small cedar every two to three years, and if
your neighbors have done as good a job as you have, eventually there will be less and
less small cedar to lop.


        We have way more deer than is “natural”, as evidenced by the pronounced
browse line 5’ up on all of the oaks, the total lack of root sprouts other bushes of any
size, the relatively high number of “spike” bucks and small antlers, the fact that deer are
commonly seen out in the daytime, as well as other indicators. The experts seem to
agree that in the Hill Country the ideal deer population is about 1 per 10 acres (about
the populations at Kerr Wildlife Management and the Bamberger Ranch), whereas the
average population in the Hill Country is closer to 1 per 3 or 4 acres. Tierra Linda
estimates have ranged as high as 1 deer per 1 acre.

        Let’s assume for the moment that we have a deer removal program (either
harvesting or trapping) with the aim of removing 15% of the estimated 2500 deer each
year for 5 years, and further assume that there will be no increase in birthrate or inward
migration as a response to the decreasing numbers of deer. In the first year, 15%
would require removal of 375 deer; if a hunter (harvester?) worked 5 days a week for 2
months taking deer, that would require him to take 9.4 deer a day. That might not be
hard if all he is doing is shooting them and leaving the carcasses where they fall, but
that is illegal. If they are to be field dressed and taken to a processor, that is surely a
full time job. At any rate, at the end of the 5 year harvesting period the deer population
would be 1109, or 44% of what it is now and still over three times the “recommended”

       But remember the assumptions I made above? They are bad assumptions; we
know better. As a population decreases with a constant or increasing food source,
there will be more food per deer and does will have more fawns. Perhaps more
importantly, the deer from the adjacent ranches will see the better food source and
lower deer population over here and jump the fence. Virtually all of TLR is within a half
mile of a border fence.

       It is almost certainly true that if we all quit feeding the deer in our back yards,
there would eventually be fewer around. But would that make any difference in the
quality of the habitat? The answer is no. Because the population would decline to the
point where the deer are at the maximum number that can survive on the “natural” food
source on the ranch, which means they would still be eating everything there is to eat
and the habitat will remain as it is.

        But that brings us to the crux of the problem; a large fraction of us like having the
deer around and they have become a rather emotional issue. If we had so few deer
that we hardly ever saw one in the daytime, many folks would feel their quality of life
was diminished, and the same probably applies to the blackbucks. So we have a
dilemma: the deer have eaten themselves and many other forms of wildlife and
livestock out of house and home and substantially damaged the ranch habitat.
Reducing the population significantly is probably impossible without high fencing the
entire ranch at significant expense. Plus, it would require a major harvesting program
that would likely be controversial.

        So, is there anything we can do to help improve the situation we have. I think
there are a few things that will help around the edges. To help make up for the lack of
wildlife cover due to deer eating the native bushes, we can carefully leave some cedar,
maybe even make a few small piles of brush (not under trees!) here and there. We can
plant NATIVE trees and bushes around, inside our fences, if deer proof, and/or in
corrals of fence outside, especially species that produce berries or beans for wildlife.
We might even consider fencing small areas with deer-proof, but small animal
accessible, fence (this would probably require Architectural Committee approval) and
allowing bushes, grasses and weeds to grow inside to provide a more natural habitat
and seed source. None of this addresses the deer population, but might help the other


        Aside from the ag evaluation they provide, which is considerable, and the
pleasure they provide for those of us who actually like cows, the cattle provide a very
important and vital function on the ranch. They eat grass! Deer only get 15% or less of
their food from grass, and then only when it is green and tender. Grass that is not
grazed accumulates to the point where a fire will have so much fuel that it will burn so
hot and high that it will catch the cedars and produce a crown fire, which is the kind of
fire that burns houses. Keeping the grass down around our houses is essential for fire
protection. Also, ungrazed grass becomes a matted, dense mulch which adversely
affects the diversity of plants that can grow under those conditions. (Of course, the
blackbuck will probably make sure it never accumulates that much.)

        Historically, ranchers have had a dim view of “environmentalists”, and, especially
in the west, sometimes vice versa. The two sides just didn’t seem to share common
values. But I must say that in all of the talks and meetings I have been to in the past
two years, I have seen none of that attitude from either side. At least around here, I
think it is a common assumption that what is good for wildlife is good for the ranch. The
best, most productive grazing land is almost by definition the best wildlife habitat; they
both benefit from plant diversity. Cattle take 87% of their food from grasses, only 13%
from forbs and browse, whereas deer eat only very small amounts of grass.

      Blackbucks eat more like sheep or goats, eating more grass than deer, but more
browse and forbs than cattle. Because of their large numbers, it is possible that the
blackbuck eat more grass on Tierra Linda than the cattle do.

       The grazing practice used at both the Kerr Wildlife Management area and the
Bamberger ranch is to have lots of different pastures in which to rotate the cattle so that
the rest period between grazing times is longer, giving new grass a better chance to get
established before being grazed. We don’t have enough fences and water sources to
do exactly what they have done, but we could probably do a better job of grazing
rotation to improve the habitat.


        Trees are the defining feature of the Hill Country landscape. They are also vital
parts of a ranch and of wildlife habitat. They provide shade for the cows and for wildlife
in the summer, they provide food (mast) for wildlife in the Fall, they contribute to plant
diversity by providing shade for plants that would otherwise not grow well in full sun,
they provide shelter for birds, squirrels, raccoons, ringtails, etc, and they provide us with
shade, beauty and enjoyment. Many of us have worked very hard to site our houses
around trees and to try to keep the trees we have healthy.

         The oak wilt that is moving through the ranch is a threat to our trees that we can
do little about. We can try to treat with Alamo when we see the blight moving toward a
special tree, or if conditions allow, we may try to trench between our prized trees and
diseased trees. But we all know that even under the best of conditions prevention is not
totally effective. And we know there is no cure. Other than the Alamo and the
trenching, the only other thing we can do to save existing trees is to NOT damage them
in any way that would allow oak wilt infected beetles to spread the disease to them.
the beetle is less active, and always painting every cut IMMEDIATELY after cutting.

        It is disturbing to see people employing tree services to cut many healthy limbs
off healthy oak trees, some doing so into April (or maybe later?). The purpose for the
pruning is not clear, but it is not beneficial to the tree. I have discussed these pruning
practices with two different Texas Forest Service foresters, plus two other experts, none
of whom thought such pruning was a good idea. In answer to the following question: “Is
there any biological reason to prune an oak tree?, one Texas Forest Service forester
answered: “No. There are only three reasons to prune a tree; for safety (if it is likely to
fall on your house or car or is blocking traffic), to repair damage caused by storms, or

       The best thing we can do for the trees is to leave them alone. The best real
hedge against oak wilt is to plant a lot of NATIVE trees. Any native tree or bush must
be watered every 7 to 10 days the first 12 to 18 months in the ground, and if it is outside
of a deer proof fence, it must be fenced for the first several years. I have a lot of other
information on tree planting for anyone interested.

Final Thoughts

        Tierra Linda is a beautiful place to live and the people make it even better. My
main goal is to make sure that everyone on the ranch has access to the best advice and
information on any topic that pertains to any aspect of the ecology of the Ranch. My
assumption is that almost everyone wants to do the right thing and really cares about
the land around us. The problem is that it is not always clear what the “right thing” is,
and there are many sources of misinformation (especially from those looking to make
money) that must be sorted through. I promise to do my best to only give information
that I believe is consistent with the thoughts and beliefs of the best experts in the field,
folks such as are listed on the first page.

       It has been over a year and a half since the first version of this paper was
published. In that time I have published over a dozen Eco Notebook articles and have
had the opportunity to talk with many neighbors about these issues. Largely as a result
of these conversations, I am more optimistic about the future stewardship of the Tierra
Linda Ranch than ever before. The problems may be significant, but there are many of
us, and together I believe we can make a difference.

The 5 BEST things you can do for the Tierra Linda Ecology.

    1. Learn all you can about the flora and fauna of the ranch. (See quote under title
    2. Clear cedar from your lot leaving only about 5% coverage. But do the clearing
       over a period of years, cutting somewhat randomly, and doing all you can to get
       grass growing back and prevent erosion.
    3. Plant LOTS of NATIVE trees and bushes, preferably a variety and preferably not
       live oaks or Spanish oaks. Again, this is a project that can be done over several
    4. Leave a few small areas of cedar as deer cover and leave a few small piles of
       brush for the rabbits, roadrunners, foxes, etc.
    5. Keep your dogs and cats at home so the wildlife will have a better chance.

The 5 WORST things you can do for the Tierra Linda Ecology
(Please note that it is not my intention here to criticize or embarrass anyone)

    1. Not care about what happens to Tierra Linda.
    2. Bring in a bulldozer and clear all of the cedar at once. This practice leaves so
       much land bare that it just invites erosion and is very difficult to recover. This is
       especially true if there is any significant slope or if the soil is very thin. If you
       can’t do it, or hire it done by hand, get a bobcat with cedar snips, and don’t clear
       everything the first year.
    3. Prune oak trees anytime other than from December 15 until February 15. Why
       not let the tree grow the way Mother Nature intended?
    4. Pick your lot totally clean of every fallen limb, twig or leaf. Not only are you
       depriving small critters of habitat, but you are inviting erosion and depriving the
       soil of very much needed organic matter. If you must make things neat, at least
       leave some areas farther from your house in a more natural ranch-like state.
    5. Shoot small animals because they have caused a minor inconvenience. We
       have wiped out enough wildlife already. Anyway, shooting is in violation of TLR


To top