1)
a) Resource used I. Exotic plant management teams II. Integrated pests management b) Number of results * Over 6,500 non-native invasive species have been documented on park lands * More than 650 invasive species have been found in marine parks
c) Number of full text results
Invasive species include all taxa of organisms, ranging from microscopic insects to 100 lb sheep.
d)  70% of documented invasive species on park lands are invasive plant species
 around 5% of park lands are dominated by invasive plants.

2)

Texas Today: A Sea of the Wrong Grasses

“I
In the ’60s when I bought this place and moved
Here from Houston, we had so many quail that
You didn’t even need a bird dog to find them,”
Mused my 85-year-old hill country neighbour. “Then,” he
Paused, his satirical glance drifting toward the mantle to
A dust-covered 20-gauge double-barrelled shotgun and a
Faded John Cowan Print of a quail hunt on a shin oak
Mountaintop of the Texas hill country, “by the early ’80s,
The quail were gone.”
“Well,” I interjected in a smug biologist’s refrain, “what
Changed?”
“Hell, I don’t know, but just before that time everybody
Planted all the maize fields to coastal (Bermuda grass), and
That damn KR bluestem came in from the highway when
They redid it.”
“I’ll bet that’s part of it,” added the old man.
What ran through agronomist Nick Diaz’s mind on a
Hot, dry Gulf Coast summer day in 1939, when he first laid
Eyes on the maroon, glistening seed heads of
Dichanthium
annulatum growing in a King Ranch pasture, was prob
-
ably a lot different than what raced through mine on April
26, 2009. As the one who first noticed the accidentally introduced African grass, and the one who helped select, increase, and release what would come to be known as
Kleberg bluestem, Mr. Diaz had high hopes for transform
-
ing dried up, grass-poor ranges into lush seas of grass. He probably envisioned pastures full of fat cattle and a buff
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ered annual bonus check, courtesy of this grass that could grow so well, and so aggressively, in the hellish windblown sands and cracked black clays of the Wild Horse Desert of south Texas.
Today’s biologists look upon Kleberg bluestem, and its
African, Asian, and Australian grass cousins brought to
Texas, with a nauseating suspicion of an ecological night
-
mare. It is akin to a viral pandemic, swallowing up chunks of what few can accurately describe with words, few thor
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oughly understand, but what used to be waves of blue
-
bonnets and paintbrushes in the spring, crimson stands of native prairie grasses in the fall, and carpets of yellow flowers interspersed by funny looking grasses whose seeds stick in socks and shoestrings. The native Texas landscape is disap
-
pearing before our eyes, under a sea of the wrong grasses.
What ran through my mind on April 26, 2009, when I saw those maroon seedheads blowing in the breeze along
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side U.S. 183 was much different than what Nick Diaz must have pictured in 1939. I wondered aloud what the hell a grass that I work to rid south Texas of on a daily basis was doing on a highway right-of-way in one of the most rural counties of central Texas a hundred miles from where it ever grew in the past
. In my 20 years of being a plant maniac, and my father’s 40 of ranching, we’d never seen it here before. Scarier still, those ripe seeds, like a pandemic land virus, ended up washing down two different creeks in the six inch rain we had two days later. I didn’t envision a pasture full of cattle, but in my mind’s eye, I can imagine one further void of quail, with fewer wildflowers and all the things that make the native Texas landscape special.
I bet that my father and I will see more Kleberg bluestem again in central Texas, and I suspect that my grandchildren will see more of it than I care to imagine. If action isn’t taken now, there’s a good chance that what’s left of the
Texas rural landscape will be a sea of the wrong grasses.
Exotic Grasses, Economics, and Ecologists
Urban sprawl be damned, another threat, quieter and of drastically underestimated importance to native habitats and wildlife, is rampaging unchecked across the Texas landscape. Past generations of Americans thrived on the beef and spoils produced in part by the greatest period of range grass experimentation and introduction known to mankind. Throughout the 1900s, and even still today,
Texas ranchers and agronomists were and are leaders in the practices of importing and planting “improved” exotic range grasses.
Why we have them is as long a story as why south Texans vote Democrat, in part just because. Old standby state
-
ments like “buffelgrass is the grass that saved south Texas” or “I wouldn’t dare ranch in Texas without exotic grasses” echo from cattlemen of my grandfather’s generation. Many still say this today, while cashing $15 per acre hunting lease payments, griping about $3 per acre cattle proceeds, and continuing to conduct land management activities wholly for cows. In contrast, progressive outfits like the King,
Temple, and Killam Ranches don’t dare plant more exotic grasses and require oil companies to reseed disturbed sites only with natives. Granted, some of these ranches used to plant exotic grasses for cattle forage. But in the past
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113 few years, as wildlife recreation increased in value and the uncontrollable spread of these grasses became apparent, they stopped and made a philosophical sea change in their management styles.
To lament the intentional planting of exotic grasses or the happenstance introduction of others in bags of dirty seed brought to Texas from Australia and other parts of the world in the early 1900s is of no use to today’s wildlife.
Finger pointing and stubbornness won’t provide habitat to the last bobwhite quail on a Gulf Coast Plain pasture or hill country mountainside. As Rachel Carson (1962) in her environmentally supercharged prose so eloquently put it, “like the resource it seeks to protect, wildlife conserva
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tion must be dynamic, changing as conditions change, seeking always to become more effective.” By all science known to us today, exotic grasses are destroying what little bit of great native wildlife habitat we have left. Spread and dominance of exotic plants such as these is second only to complete destruction of habitat as the most troubling wildlife conservation topic worldwide (Wilson 1992).
Stepping on toes and pointing fingers about the wisdom of past exotic grass introduction to Texas will certainly be ineffective, but a radical change in land management in our state, and cessation of practices that further spread exotic grasses, might be good changes for our generation. The time is now for Rachel Carson’s suggestion of becoming more effective, before we have no real native habitats left.
Yesterday’s Exotic Grass Solution and Today’s Problem
Exotic grasses cause problems to wildlife, native plants, and the natural ecological cycles of any area in which they occur. Texas today is far different from Texas when these plants were introduced. In the early 1900s, Texas was rural, with small farms surrounded by large contiguous ranches, and probably fewer paved roads statewide than today exist in Harris County (surrounding Houston) alone. A typical ranch was stocked to the gills with cattle, supplemented with sheep, goats, or horses, and was running out of grass long before the first exotic buffelgrass (
Pennisetum ciliare
)
seed was planted. Soil erosion and clouds of dust would’ve made an ecologist of the time write a much different article than this, had the economy permitted such luxury. Native
Texas rangelands and Texas grazing styles of the time didn’t mesh well with one another. In addition, renovat
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ing and revitalizing fires that had sustained and promoted many native plants and habitats had long been suppressed; coupled with the everyday grazing by cattle stocked too heavily in pastures recently rimmed with barbed wire, the situation made for a countryside running low on grass and shorter on dollars.
In the early 1900s, King Ranch obtained Rhodes grass
(
Chloris gayana
) seed from South Africa. What was a novel idea and a trial to increase forage in overgrazed pastures led to a program that, like many other King Ranch ideas, worked and worked well. Rhodes grass almost completely died out in south Texas in later years owing to an accidental exotic insect introduction, but the potential benefits in forage production by exotic grasses were by then well- known. Soon, federal and state agencies had joined the effort, and by the 1950s every grass from every part of the world that a cow would eat was being evaluated or planted across Texas. Old Soil Conservation Service land management plans included the common recommendation to chain, plow, or grub brush and “seed to yellow (King
Ranch) bluestem” (
Bothriochloa ischaemum
) or “seed to buffelgrass.” Releases of exotic grass products from agencies to producers bore the proud names of their developers, like
King Ranch and Kleberg bluestems. Literally hundreds of thousands, if not millions of acres of the Texas landscape have been planted to these grasses, principally Rhodes grass,
Old World bluestems (
Bothriochloa
and
Dichanthium
spp.), buffelgrass, and Bermudagrass (
Cynodon dactylon
). Con
-
servation efforts like the Conservation Reserve Program resulted in more exotic grasses being planted than most care to acknowledge. Other countless acres of overgrazed native rangelands were subsequently invaded by the ecologically unchecked spread of these grasses, or through accidental dispersal of seeds by livestock, ranchers, and equipment.
Some of the grasses brought to Texas stayed where they were put; Rhodes grass is not much of a problem today, and Kleingrass (
Panicum coloratum
), a later introduction, usually behaves itself. Others like guineagrass (
Urochloa
maxima
) and Lehmann lovegrass (
Eragrostis lehmanniana
)
were planted here and there, but also got loose accidentally.
Ask Rio Grande Valley birders what they think of guinea
-
grass these days, or a west Texas rancher what Lehmann lovegrass is good for. Neither of these exotic grasses suits the needs of today’s users of the landscape. Guineagrass suppresses plant diversity so that birds avoid areas infested with it, and Lehman lovegrass is at best a poor forage that chokes out better grasses.
To the livestock producers of last century, many exotics were miracle grasses; they established easily, grew aggres
-
sively, and took abusive stocking rates in stride. Wildlife, as an afterthought, was generally thought to have benefitted from these grass introductions, as some ground cover was obviously better than none. An environmental priority of the time, the nationwide soil conservation effort had been largely accomplished with their use. Obviously, wildlife weren’t the concern then as they are today, despite the eloquent writings of Aldo Leopold (1949) and other far- sighted conservationists. Annual lease payments of $15 per acre for hunting access to ranches weren’t even a dream to most landowners, and it’s rare that someone’s conservation ethic completely trumps the need for a roof over their head or food on the table. But what was a winning necessity in
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115 also show alarming population reductions at the same time that exotic grasses have increased. Exotic grasses are the principal threat to many endangered plants in Texas, like slender rush-pea (
Hoffmannseggia tenella
), south Texas ambrosia (
Ambrosia cheiranthifolia
), or Zapata bladderpod
(
Lesquerella thamnophila
). While much of this important biodiversity is becoming a rare sight in Texas, exotic grasses aren’t. Unless you’re lucky enough to visit one of the last big ranches in Texas, exotic grasses are the staple view, whether the venue be a highway roadside, urban alleyway, or rural farmstead.
Exotic grasses today are negatively influencing or invad
-
ing what little of the native landscape we have left. In south
Texas, for instance, almost any oil rig caravan, piece of mowing equipment, wind farm service truck, or hunting rig sports a healthy collection of buffelgrass and Kleberg bluestem seeds in the grille, ready to be deposited on the plethora of new drilling-site roads, wind farms, highway rights-of-way, or gas pipelines dissecting the vanishing former expanses of native plants. Most experts agree that a big factor in many native habitats being overtaken by exotic grasses is the increase in disturbance and the incursions by wind farms, power lines, roads, and urban sprawl into formerly contiguous, unfragmented habitats.
Another undeniable cause is that many of these grasses are still being planted, and with greater efficiency and purpose than ever before. Buffelgrass is still probably the biggest rangeland seed crop sold statewide. Genetic and agronomic engineering of many exotic grasses has made them even more vigorous than they naturally were. Cold- tolerant buffelgrass is one scientific accomplishment feared by many ecologists; luckily, these cold-tolerant cultivars have had only modest success in the buffelgrass market.
Guineagrass is commercially disguised as “green panic grass” and frequently sold to unsuspecting consumers, who’d never consider planting guineagrass if it were labeled as such. Today’s Bermudagrass cultivars possess downright scary adaptations for vigor and spread. As a result of federal
Clean Water Act provisions designed to prevent soil ero
-
sion, the giant buyer of the grass seed market, the Texas
Department of Transportation (TxDOT), is forced to plant exotics at the completion of a highway project if native seed is not immediately available in the necessary quanti
-
ties. Mining companies include Old World bluestems in reclamation seed mixes for wildlife habitat on unsuspecting ranches because the seed is cheap. Landowners mistakenly plant buffelgrass seed to create better quail habitat, despite solid research findings in top scientific journals that areas infested with it support just half the quail of native plant communities (e.g., Flanders et al. 2006).
Unless changes in land-management mindsets are made, exotic grasses may no longer be one of the issues facing conservationists; they may well become the issue.
The
issue today is that landowners and agencies must change how they use the Texas landscape if they want to preserve natural landscapes. Some changes would be devastating. The still important cattle industry needs grasses like buffelgrass and bermudagrass to thrive; that use cannot realistically be compromised, but other careless ones can. State agen
-
cies such as TxDOT can stop planting exotic grasses on roadsides, ever
. It may not be easy, and may take changes in how things have always been done, but most all agree it is feasible.
Landowners can put their foot down to oil and gas and energy giants who whine about the cost of restoring land with native plants after destructive exploration and petroleum production practices, and refuse to allow them to plant cheaper exotic grass seed. Few people can realisti
-
cally be sympathetic to oil companies over the difference in restoration costs of a couple hundred dollars an acre on drilling sites that produced thousands of dollars of profits each day for the most profitable companies in the world.
The wisdom of fragmenting and dissecting thousands of acres of native habitat with environmentally friendly wind energy and accompanying transmission lines should also be examined with a view toward vegetation and ecosystem importance before we so readily fall head over heels for it. Hay production involving known problematic exotic grasses like Kleberg bluestem should cease, not by regula
-
tions but through education. Many a rancher inadvertently plants his ranch with Kleberg bluestem by feeding cheap trucked-in hay to cattle.
A billboard proposed by one agency all too aware of this problem is to read “hello buffelgrass, goodbye quail.”
This effort is part of an educational campaign to convince
Texans not legislatively, but sensibly, to think twice about their actions involving exotic grasses. Along with educat
-
ing the masses and protecting the few relict native sites we have left, researchers also need to devise better solutions to improve the widespread problematic areas that exist today and slow the exotic grass invasion. It will take this multipronged approach to make a difference.
Turning the Exotic Grass Tide
Smoke from the fire of the “patch” burn in a remote pasture of a 13,000 acre La Salle County ranch no doubt caused a few calls to the Cotulla volunteer fire depart
-
ment. Given 2008’s uncontrollable 50,000 acre buffel
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grass-assisted inferno in the area, who can blame the callers? But this small fire, a prescribed one, was over quickly enough that nobody got too worried about it. A herd of Mexican steers will be camped out on the burned area in a few days, tromping through the ashes to eat the fast-emerging, tender sprouts of buffelgrass and Kleberg bluestem. The intent here is not T-bones and hamburgers, but to kill or suppress the exotic grasses so native plants can once again grow here. The practice goes against all
June 2010

3)
ZEBRA MUSSELS CHANGING GREAT LAKES ECOSYSTEM
In a just-published series of scientific papers, university researchers and scientists from the Great Lakes Environmental Research Laboratory in Ann Arbor, Mich., have documented basic changes in the food chain in zebra mussel-infested waters of Lake Huron's Saginaw Bay that threaten water quality and healthy fisheries across the Great Lakes ecosystem. The lab is run by the Commerce Department's National Oceanic and Atmospheric Administration.
In general, the research shows an alarming shift in how energy and nutrients are routed through the food chain. Results show that Saginaw Bay's energy base is no longer dominated by phytoplankton because these microscopic, free-floating plant cells are choice food for zebra mussels, which are able to selectively filter the cells out of the water.
The spread and growth of zebra mussels have decimated this important free-floating part of the food chain, raising concerns that all of the bay's fish stocks may suffer.
Zebra mussels are also encouraging growth of harmful blue-green algae by rejecting them as food, thus giving them a competitive advantage over less abundant algae that are eaten by the mussels. The mussels may also release nutrients that encourage algae growth, especially blue-green algae.
This in addition to a sudden change from a free-floating to a bottom-dominated food base may force scientists and decision- makers to reassess current models used to guide the management of water quality, fisheries and toxic contaminants throughout the Great Lakes region.
4)
1)are author names include …in some sites some of the authors are included while in others are not
2)are authors credintals included no they tend to ignore
3)in many of the sites the date of edition is not evident
In many sites they are not credible since they do not have the enough information to support their information