Tag Archives: native grasses

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Some research that might be of interest…

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My Google Scholar alert feed tossed a couple of items my way  that might be of interest. They are in PDF format, so you can read them online or download them for future reference:

Tricky partners: native plants show stronger interaction preferences than their exotic counterparts.

Citation: Coux, C., I. Donoso, J. M. Tylianakis, D. Garcı´a, D. Martı´nez, D. M. Dehling, and D. B. Stouffer. 2021. Tricky partners: native plants show stronger interaction preferences than their exotic counterparts Ecology 102(2):e03239. 10.1002/ecy.3239

Main takeaway (my interpretation): Increasing presence of exotic plants may put rare native plants at higher risk of extinction.

(Caveat: my browser says the site is not secure. However, I have several security programs that (hopefully) would mitigate. the risks).

That being said, the article is from a group of scientists from New Zealand, Germany and Spain who looked into the interactions that native and exotic plant species had with other plant species.

Exotic species interact with many partners with which they have not coevolved, and it remains unclear whether this systematically influences the strength of neutral processes on interactions, and how these interaction-level differences scale up to entire networks. To fill this gap, we compared interactions between plants and frugivorous birds at nine forest sites in New Zealand varying in the relative abundance and composition of native and exotic species, with independently sampled data on bird and plant abundances from the same sites

The results found that native plants’ interactions with birds were both more positive (preference for) and negative (avoidance of). Their analysis suggests that the blending of species communities through dispersal of exotics into native plant communities might result in an increase of neutral interactions between birds and native plants or exotic plants.

This could make rare species more vulnerable to this loss of selectivity and to greater randomness in the identity of their interaction partner.

So there’s another argument for getting rid of invasives.

Moving right along, here comes

Where Have the Native Grasses Gone: What a LongTerm Repeat Study Can Tell Us about California’s Native Prairie Landscapes

…found that native grass cover decreased dramatically (especially on the valley floor), exotic grass cover fluctuated widely over time, while both native and exotic forb cover increased over time. The findings support the notion that prior grazing management practices may have supported the former stands of Stipa pulchra.

… Several trends became apparent when the data from the three periods are viewed together. Both native and exotic forbs increased between each data collection. There were consistently more native forbs than exotic ones and native grasses decreased in cover. Though exotic grasses fluctuated, they always made up a greater amount of cover than their native counterparts. Lastly, cover of bare ground fluctuated and shrubs declined. The Fisher’s Exact test of the increases and decreases of forb and grass cover across quadrats from 1981 to 2015 had a p-value of 0.00012 indicating that we can reject the null hypothesis of independence…

… native bunchgrasses have declined dramatically since the end of the ranching era. Simultaneously, native forbs have increased (at least temporarily), especially on the valley floor. Our findings also suggest that the historical ranching practices in LJV likely supported the excellent stands of Stipa observed in the valley prior to release from grazing. These findings are in agreement with those of previous long-term studies in other parts of California that also found a decline in Stipa cover on lands released from grazing. (emphasis added).

If one were to generalize the conclusions of this study to Texas, where this writer resides, I would say that the presence of large stands of Prickly Pear (Opuntia sp.). and Texas Cedars (Juniperus ashei) as the dominant species in large parts of Central Texas is probably due to past practices of overgrazing, similar to the presence of the native bunchgrasses in California has been attributed to the previous grazing practices in the study cited above.

However, I do not believe that the answer to the problem is to bulldoze the soil away and to cover the land with non-permeable surfaces like buildings and asphalt parking lots.  One can develop land while leaving large portions of native plant species intact, and without replacing them with crappy myrtles and Nandina plants.

postscript:

One of the references used in the article on California grasses was California’s Fading Wildflowers  by Richard A. Minnich. The table of contents and lists of illustrations and tables and preface are available for open access, but the book itself costs a hefty $128.00.  Another reference was Terrestrial Vegetation of California. California Native Plant Society Special Publication Number 9 (pp. 733–760). Sacramento, California., which is not on the web.

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annuals, butterflies, Drought resistant, grasses, insects, perennials, pollinators, Vines, wildflowers , , , , , Leave a comment

In the heat of the summer

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I seem to suffer from Gilligan’s Syndrome – what starts out as a five minute walk outside to water the plants in their containers that I am hoping will hold on until cooler weather comes (September? October?) turns into an hour or more photo safari. Sometimes I go beyond the confines of my yard, sometimes not.

Ruellia nudiflora, for instance, has suddenly been blooming like crazy. A Passiflora incarnata volunteer popped up in the mulched bed across from the Passiflora lutea and Passiflora suberosa, and started putting out blooms. The Malvaviscus arboreus var. drummondii continue to bloom, as do the Salvia greggii, Lantana urticoides, Scutellarria wrightii, Salvia farinacea, and Conoclinium greggii. In the “nursery,” several Asclepias milkweeds have bloomed or budded, along with Tetraneuris scaposa. In the gravel pathway, I had to (reluctantly) trim the Boerhavia coccinea back to allow human passage. The Fallugia paradoxa has put out a few blooms and plumes, and the Pavonia lasiopetala has been a pleasant surprise with its hibiscus-like pink blossoms.

We have Liatris punctata still in bloom, Melampodium leucanthum, Asclepias texana, and a native grass that I have been calling “Indian Grass,” (turns out that is the common name for Sorghum nutans. The Aloysia gratissima has attracted pollinators, as has the Anisacanthus quadrifidus, and behind the fence, the Proboscidea louisianica or “Devil’s Claw,” has held out with a bloom or two. The Glandularia bipinnatifida has come up in various spots, too low for the mowers’ blades most of the time. As can be seen in some of the photos, these native plants of Texas, most of which are not receiving any supplemental watering, provide food for Bumblebees, butterflies, and even hummingbirds, lizards, and wasps. I even went out and over the course of several days, harvested enough Diospyros texana fruit to make a Texas Persimmon Loaf. The slide show that follows includes photos taken the week of August 10 – 16, 2020

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A mid-Summer’s nightmare

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I have seen the best plants of my eco-region driven into ghettos of greenbelts, invaded by non-native plants, poisoned with herbicides…

I see public areas, along roadways and in park areas, mowed so low that the grass is turning brown and burnt by the sun, despite sprinklers and watering, and occasional rains brought on from sub-tropical weather disturbances in the Gulf of Mexico.

I see the berm behind my house, where a stand of wildflowers in bloom had been cut down in late May while the ground was still wet, and where the native Silver Bluestem grass, which had once dominated the berm, had returned, mowed down in late July, parched and sere under the August sun. Because the contracts signed say they have to mow a certain number of times within certain calendar limits.

I have written emails to my HOA and the Municipal Utility District, and received no response. If a tree falls in the forest, or a native plant goes extinct or disappears from a region because of destruction of habitat, does it make a sound if there are no humans to hear it cry out?

And yet, life goes on.

I have seen the Clematis drummondii, with their achenes in showy white plumes, and must make a note to get out of the house for a photo safari soon, while this year’s show is still on. I have seen the Passiflora  vines and the Gulf Fritillary butterflies in their back and forth movements between fertilization, egg-laying, larvae consuming the plant, and adult butterflies dancing about. I have seen the native plants in my yard, both those intentionally planted, and those volunteers who have been recognized and protected, thrive or at least survive.

And I have seen the birds drinking from the water fountain, having been provided with plants that provide food (and insects that thrive and provide food as well), shelter, and a place to build their homes. I have seen the hummingbirds zooming about, grabbing sips of nectar from the salvias, the Texas Red Mallows, and the Flame Acanthus (though this year, I’m afraid I haven’t quick enough to focus and click on the camera quickly enough to capture one in mid-flight.

And as the globe warms, I wonder what changes I’ll be seeing in the plants that thrive in this area, and whether enough humans will start to think outside the box of “that’s the way we’ve always done it,” or “that’s the I’ve always heard it should be,” to make a dent in the greenhouse we are living in.

But enough of that. Time for some photos – some OK, some not so great, but the subject matter supersedes this one’s talents:

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Bouteloua gracilis – Blue Grama

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Bouteloua gracilis - Blue Grama

Bouteloua gracilis – Blue Grama

Blue Grama is one of several native grasses that is being pushed as a native turf alternative to St. Augustine or Bermudagrass.  It grows in bunches and forms mats. Hairy Grama is similar in appearance, but has a “stinger” at the end of the seedhead, which Blue Grama lacks.

This particular specimen was photographed alongside the curb, where I have tried, mostly unsuccessfully, to establish Buffalograss between the sidewalk and the curb. I’ve used the Blue Grama seed to attempt to fill in the patchy spots that the Buchloe dactyloides seems to be prone to.

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Elymus canadensis – Canadian Wild Rye

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Elymus canadensis - Canadian Wild Rye

Elymus canadensis – Canadian Wild Rye

This is a perennial grass with a distinctive pattern of its spiky seedheads. It is shade tolerant and mildly drought tolerant.  It grows to about 2-3 feet high.

This photo was taken July 14 on a field trip to Taylor Park at Lake Granger in Williamson County, Texas. We saw a lot of this grass on the nature trail.

As always, clicking on the image opens a larger picture.