Thursday, August 28, 2014

Is Stiltgrass Killing our Toads? Yes, but indirectly.


Japanese stiltgrass infestation

Invasive plant impacts on native plant species and on community structure is well documented.  Invasive plants direct-impacts on native wildlife through reduction in forage availability is also fairly straightforward.  What is less understood is the more complex indirect-impacts on wildlife from invasion by exotic plant species.

We've discussed these types of indirect-impacts to wildlife from invasive plants here on this blog several times.  Buckthorn infestations alter the distribution and movement patterns of predators, contributing to the decline of amphibians in the upper Midwest LINK.  Bush honeysuckle can change the competition balance in amphibians, leading to dominance by one native species, to the detriment of many other species LINK.  Invasive plants of prairies, such as knapweed and leafy spurge, alter the habitat structure in such a way that promotes increased web building by native spiders, leading to a trophic cascade that impacts native flora and fauna by throwing everything out of balance LINK.  In a presentation at this year's Illinois Invasive Species Symposium, Dr. Matt Allender indicated that the reduction in habitat quality from invasive plant species could be contributing to the decline in health and wellness for box turtles, which makes them more susceptible to diseases LINK.

Of course, sometimes our native wildlife can facilitate invasive plants, as is the case with deer and garlic mustard LINK.


A recent article published in the journal Ecology brought to light evidence that Japanes stiltgrass is indirectly leading to increased mortality of young toads.  Worse yet, this indirect impact is greatest felt in forests, a preferred habitat for young toads and traditionally a stronghold for survivorship.  Now habitat that once was a source, could be a sink.

So how and why is this happening?  Basically stiltgrass infestations are superb habitat for wolf spiders and wolf spiders are super predators and they love to eat young toads.  So more stiltgrass = more wolf spiders = less toads.  A press release published in Science Daily (LINK) elaborates:

Spiders are incredible predators, Maerz explained, and they eat everything -- even other spiders. That typically keeps spider populations in check, Maerz said, but Japanese stiltgrass is "kind of like a tall shag carpet," and it provides the cannibalistic spiders refuge from one another. The accumulation of large, predatory spiders in these invaded habitats then results in higher mortality for small toads that have recently emerged from wetlands... spider densities were 33 percent higher and toad survival decreased by 65 percent... with the presence of stiltgrass. The presence of stiltgrass alone, in the absence of spiders, did not affect toad survival.  "Spiders are actually tremendously important and incredibly abundant predators on the forest floor, and they will eat many of the small species that live there, so this effect is unlikely to only influence toads,"

This research made the cover of the journal Ecology and for good reason!  Just to notice and speculate about this type of interaction is impressive enough, but then to design a study that teases out other impacts and clearly demonstrates this important impact and result from invasion is admirable. 

The citation for the research is:

Jayna L. DeVore, John C. Maerz. Grass invasion increases top-down pressure on an amphibian via structurally mediated effects on an intraguild predator. Ecology, 2014; 95 (7): 1724

Amphibians, as a suite of species, are in global decline. This trend holds true here in Illinois as well. Water pollution, climate change, and habitat loss are all contributing to this decline and now we are starting to understand that invasive plants not only impact forage availablity for wildlife but, in addition, can cause much more complex changes to invaded areas that are not as easy to understand or mitigate.  We need more research like this.  We need to understand these impacts, just to allow us to be able to prioritize our control efforts and develop practices and protocols to better manage our native wildlife.

Tuesday, August 26, 2014

Invasive brush gives way to 500 volunteers

The La Salle News Tribune recently published a nice article about the Conservation Foundation partnership with a for-profit company to remove invasive species from Dayton Bluffs Preserve.  

The original article can be found HERE.   

Invasive brush gives way to 500 volunteers  

The buckthorn and honeysuckle didn’t stand a chance last Tuesday against an army of more than 500 volunteers at Dayton Bluffs Preserve on the east side of Ottawa.  The Conservation Foundation bought this 253-acre property last year and has been chipping away at restoration, which mostly means cutting and killing non-native plants in favor of native species.

On Tuesday, it had a little help from Fairmount Santrol, which has sand operations in the area and was holding a sustainability summit this week in Schaumburg. Fairmount bused attendees and equipment to Dayton Bluffs for a “Day of Caring” volunteer effort.

After getting coached on how to identify and cut buckthorn and honeysuckle, they went at it. “We had to run up to the store to get more loppers for them to use,” said Beth Lestock, Fairmount corporate sustainability development coordinator from Chesterland, Ohio. The army included employees and corporate partners of Fairmount, about 540 in all, with some from Mexico, Denmark and China, Lestock said.

“It’s just incredible,” said Tara Neff of The Conservation Foundation. “It’s like an Army Corps.”

The mound of invasive shrubbery grew taller and was hauled to wood chippers, also supplied by Fairmount. The work was not window dressing. It was to remove a scourge. Other professional crews joined the effort, sawing down honeysuckle and buckthorn hugging the light-rich zone along the woodland edge.

This will allow native species to grow, said Jeff Duncan, a volunteer with The Conservation Foundation.

“We pretty much try to keep the invasives out and let the natives come back on their own,” Duncan said.

The roots, seedlings and seeds of the natives are already there, waiting for opportunity, he said.

“We just need to give them more sunlight rather than force something to live there that wouldn’t normally live there,” Duncan said.

The Conservation Foundation purchased the property last year for $2 million and is leasing it to the City of Ottawa to manage as a public preserve.

Jeff Dankert can be reached at (815) 220-6977 or perureporter@newstrib.com. Follow him on Twitter @NT_Peru.

Monday, August 18, 2014

New Sprayer Calibration Calculator App

The University of Illinois is introducing the new Sprayer Calibration Calculator App developed by Scott Bretthauer, Extension Specialist, Pesticide Safety Education.

This app assists applicators in calibrating a pesticide sprayer. The app can be used for aerial, ground, turf, and boomless applications. It includes functions for determining the required nozzle flow rate, splitting that flow rate among different orifice sizes on an aerial boom, and calculating a required pressure to achieve a specific flow rate.

It also has a function to convert values and rates for some commonly encountered variables and to determine maximum and minimum operating speeds based on nozzle capacity.

It is available for free in both Apple iOS and Android formats.

Apple iOS - https://itunes.apple.com/us/app/sprayer-calibration-calculator/id899216316?mt=8
Android - https://play.google.com/store/apps/details?id=edu.illinois.extension.spraycalculator&hl=en  

Tuesday, July 22, 2014

Asian Carp vs. Commercial Fishermen 2.5M lbs of carp now out of Illinois

It’s been four years since the discovery of an Asian carp between the electric barriers and    Lake Michigan. That’s when the state went into emergency mode. They hired a select group of Illinois commercial fishermen.  And as our Nancy Loo reports, they’ve now taken two-and-a-half MILLION pounds of Asian carp out of Illinois waterways.  In the backwaters of the Illinois River near Starved Rock State Park, there are fewer Asian carp jumping this year...

See the full story and watch a video at:
http://wgntv.com/2014/07/21/asian-carp-vs-commercial-fishermen/

Tuesday, July 15, 2014

Phenology Report for July 15, 2014

From time to time, we will be reporting on the development of invasive plants across Illinois, informing readers about what is in bloom, leafing out, setting seed, senescing in different regions of the state.  Feel free to add to the knowledge by emailing chris.evans@illinois.gov and letting me know what the plants are doing in your area of Illinois.
Phenology Report for July 15, 2014*
(Contributors include Cathy McGlynn, Mike Davis, Karla Gage, Paul Bane, and David Crady)
*Report based upon observations between July 10-15, 2014
Southern Illinois
  • Teasel, Dipsacus follonum and D. laciniatus - Teasel is in full bloom right now.  You can see both the purple flowering common teasel and the white flowering cut-leaf teasel along roadsides and in old fields.
  • Purple loosestrife, Lythrum salicaria - Purple loosestrife is starting to bloom in southern Illinois.
  • Poison hemlock, Conium maculatum – Poison hemlock has finished flowering and the seeds are starting to dry as the plants senesce.
  • Reed canarygrass, Phalaris arundinacea – Reed canarygrass is in full bloom right now.  It can be found in open, wet areas.
  • Johnsongrass, Sorghum halapense - Johnsongrass is in full bloom right now in southern Illinois.  Look for it in roadsides and other open, disturbed areas.
  • Garlic mustard, Alliaria petiolata - Garlic mustard fruits are drying and seeds are falling off of the plant, making it extremely easy to spread garlic mustard.  Take care to clean you shoes and check your pant cuffs after walking through an area with garlic mustard.  Interestingly, several populations of garlic mustard still had a few flowers, even when fruits were drying lower down on the plant.
  • Japanese stiltgrass, Microstegium vimineum - Stiltgrass is starting its rapid summer growth, but has not yet begun to flower.  Now is a good time to consider treatments.
Central Illinois
  • Wild parsnip, Pastinaca sativa – All wild parsnip plants are seeding.  Much of the seed is darkening, but not much is falling to the ground yet.
  • Poison hemlock, Conium maculatum – Poison hemlock is done flowering in central Illinois.  For the most part, seds haven't matured yet (all seeds seen are yellowish-green) but are getting close..
  • Canada and Bull thistle, Cirsium arvense and C. vulgare – Canada thistle is seeding and the see is starting to fly off.  Bull thistle is just beginning to form a head, but not flowers yet.
  • Yellow and white sweet clovers, Melilotus spp. –Yellow sweet clover has many going to seed with very few showing flowers; seeds are dark and beginning to fall.  White sweet clover still has plenty with flowers.  For those beginning to seed, the seeds still look very green.
  • Cutleaf teasel, Dipsacus laciniatus – Teasel is starting to form heads, but no flowers have been seen yet.
  • Bouncing bet, Saponaria officinalis - Bouncing bet is just flowering now, the perfect time to control it.

 Northeast Illinois
  • Cutleaf teasel, Dipsacus laciniatus - Teasel buds have formed and plants will likely be blooming within the next two weeks.
  • Queen Anne's lace, Daucus carota - Queen Anne's lace is in full bloom.  Look for this plant along roadsides, in pastures, and other open, grassy areas.
  • Orange daylily, Hemerocallis fulva - Daylilies are in full bloom right now.  These plants spread from remnant plantings and can be found in open areas.
  • Purple loosestrife, Lythrum salicaria - Purple loosestrife is just starting to bloom in the wetlands of Northeast Illinois.
  • ** Update - Donald Wilson reports Wild Parsnip, Pastinaca sativa, is also in bloom in NE IL

 Northwest Illinois
  • Yellow and white sweet clovers, Melilotus spp. - White sweet clover has finished flowering, with about 25% in seed and the rest will be in seed soon.  All yellow sweet clover is in seed.
  • Bush honeysuckle, Lonicera maackii - Bush honeysuckle is beginning to go to fruit.
  • Japanese barberry, Berberis thunbergii - Japanese barberry has not yet flowered.  Keep an eye out for this plant in wooded areas throughout the region.
  • Multiflora rose, Rosa multiflora - Multiflora rose buds have begun to form in the woods.  Look for this plant to flower soon.

Monday, June 23, 2014

Thousand Cankers Disease (TCD), deadly to Black Walnuts, found in Indiana

Thousand Cankers Disease (TCD) was recently discovered in Brown County, Indiana.  For a news article on the find go HERE.

Thousand Cankers Disease is a serious threat to Black Walnuts throughout the Eastern United States, including Illinois.  This disease is native to southwestern United States, where it is a minor pest on the native western walnuts, but it is deadly to the Black Walnut, native to the Eastern United States.  This is both a huge ecological and economic threat because of the importance of Black Walnut in our forested ecosystems and its high value as a timber product.

The diease has now been found in seven eastern states.  Surveys in Illinois have not found any Thousand Cankers Disease to date.  Illinois has external quarantines set up to restrict the importation of Black Walnut material from states with TCD.  Please check with the Illinois Department of Agriculture for more details about the quarantines.

The fungus, Geosmithia morbida, typically associates with the Walnut Twig Beetle.  This tiny beetle spreads the fungus from tree to tree.  What is particularly scary about the discovery of the fungus in Indiana is that it was discovered on weevils, making it the first time the fungus was found associated with an insect other than the Walnut Twig Beetle. 

Additional information from Illinois about TCD can be found at:
http://www.agr.state.il.us/Environment/Pest/tcd/TCD.pdf and
http://wwx.inhs.illinois.edu/files/3613/7484/6967/TCD_ID_TO_PRINT_handout_IL_version.pdf

Monday, June 16, 2014

Phenology Report for June 16, 2014

From time to time, we will be reporting on the development of invasive plants across Illinois, informing readers about what is in bloom, leafing out, setting seed, senescing in different regions of the state.  Feel free to add to the knowledge by emailing chris.evans@illinois.gov and letting me know what the plants are doing in your area of Illinois.
 
Phenology Report for June 16, 2014*
 
(Contributors include Cathy McGlynn, Karla Gage, Marilyn Leger, Eric Smith, Mike Davis, Matt Balk, Paul Bane, David Crady, and Mike Daab)
*Report based upon observations between June 5-16, 2014
 
Southern Illinois
  • Garlic mustard, Alliaria petiolata - Second-year plants are senescing, becoming chlorotic; siliques have matured and seeds are hardening. Seeds have not yet begun to dehisce as of June 3. Once this occurs, contact with the plant is not advised because seed are easily spread.
  • Bush honeysuckles, Lonicera maackii and L. morrowii - Amur honeysuckle has passed flowering stage and the fruits are beginning to form, still small. Morrow's honeysuckle has bloomed and now has bright red and orange fruits.
  • Japanese honeysuckle, Lonicera japonica – Japanese honeysuckle is in full flower now.
  • Border privet, Ligustrum obtusifolium - Flowering stage has passed peak and fruits are beginning to form.
  • Purple wintercreeper, Euonymus fortuneii - Plants that have enough available light (high in tree canopies or in open wooded edges) are producing flower buds.
  • Chinese yam, Dioscorea polystachya, syn. D. oppositifolia - Plants are beginning to produce flower buds. The beginning of bulbil production still has not been observed. Plants are climbing rapidly into the tree canopy as new plants continue to emerge from last year's bulbils.
  • Teasel, Dipsacus follonum and D. laciniatus - Teasel is bolting and almost at the stage of flowering. In fact, you could likely find a few plants already in flower
  • Japanese stiltgrass, Microstegium vimineum – Stiltgrass is 4-5 inches tall and getting ready to start its rapid summer growth. Look for it to rapidly increase in height over the next few weeks.
  • Poison hemlock, Conium maculatum – Poison hemlock has been in full flower but many of the flower heads are starting to fade and produce seeds.
 Southeast Illinois
  • Yellow sweet clover, Melilotus officinalis – Yellow sweet clover is in full bloom
  • Crown vetch, Securigera varia – Crown vetch is in full bloom, along with hairy vetch, Vicia villosa
  • Cypress spurge, Euphorbia cyparissias – Cypress spurge is in full bloom
Central Illinois
  • Garlic mustard, Alliaria petiolata – Plants are starting to have darkened seed pods.
  • Wild parsnip, Pastinaca sativa – Wild parsnip is in full flower right now and we have pulled a few that were passed flowering and had immature seeds.
  • Poison hemlock, Conium maculatum – Poison hemlock is in full bloom but seeds have not been observed yet.
  • Reed canarygrass, Phalaris arundinacea – Some heads starting to produce seed but all are still light and immature, most are flowering, and some are just sending out their flower stalk.
  • Canada thistle, Cirsium arvense – Canada thistle is starting to flower fully now. Bull thistle, Cirsium vulgare, is still low to the ground without much of it shooting up the center stalk yet
  • Japanese honeysuckle, Lonicera japonica – Vines are just starting to flower in a few areas.
  • Crown vetch, Securigera varia – Crown vetch has been flowering for a few weeks now, though there is still time yet before it develops seed.
  • Yellow sweet clover, Melilotus officinalis –Yellow sweet clover is in full flower and some are ending their flowering. Alfalfa and white sweet clover are also beginning to flower out.
  • Cutleaf teasel, Dipsacus laciniatus – Teasel is starting to bolt. Some that were low to the ground just last week, are now 3 to 4 ft tall.
 Northeast Illinois
 Northwest Illinois
  • Yellow sweet clover, Melilotus officinalis – Plants are beginning to flower but seed pods not completely formed yet. White Sweet Clover is not in flower yet but stands at mature height.
  • Multiflora rose, Rosa multiflora – Established plants are beginning to flower. Leaves are fully expanded on newer recruitment.
  • Garlic mustard, Alliaria petiolata – Plants have finished flowering and seed pods have fully developed. In drier spots leaves are beginning to senesce.
  • Amur honeysuckle, Lonicera maackii – Plants are beginning to flower in dry uplands and are leaves have fully expanded in wetter areas.