- Author: Ben Faber
by UC ANR Staff Writer
Publication helps growers identify the rodent species on their properties, their life cycles and tools available to control them
Burrowing rodents can cause extensive and expensive damage to orchards and crop fields. To manage the pests without chemicals used on conventional farms, organic growers can consult a new publication from UC Agriculture and Natural Resources scientists.
“Burrowing Rodents: Developing a Management Plan for Organic Agriculture in California” outlines management within organically acceptable methods using an integrated pest management approach.
California ground squirrels, pocket gophers and meadow voles are the three most common species that cause damage. Squirrels chew on seedlings, fruit and nuts, killing young trees and reducing crop yields. In addition to plants, ground squirrels, pocket gophers and voles can chew on irrigation lines, and their burrow systems can channel water away from plants and erode the soil. The holes and mounds created by burrowing rodents pose hazards to farmworkers and farm machinery.
This publication helps growers identify the rodent species on their properties, their life cycles and tools available to control them.
“Growers can read about how to effectively select and set a range of traps for burrowing rodents,” said co-author Margaret Lloyd, UC Cooperative Extension small farms advisor for the Capitol Corridor. “Traps are an important tool for organic management, but maximizing control comes from integrating knowledge. Here we present information about rodent biology, trap efficacy, biocontrol, habitat management, plant protection and other approaches to collectively manage the pest problem.”
In the publication, Lloyd and Roger Baldwin, UC Cooperative Extension wildlife specialist in the UC Davis Department of Wildlife, Fish and Conservation Biology, review the effectiveness of commercially available traps – where to place the traps, whether to use attractants, and methods of euthanizing the animals.
They also offer cultural techniques for deterring rodents such as flooding fields and deep ripping soil to destroy burrow systems. Crops for orchard floors or cover cropping can be selected and managed to minimize habitat that protects and encourages gophers and voles.
For biological control, they suggest barn owls, raptors and snakes might be able to assist, but warn growers that predators alone will not be able to eat enough of the rodents to reduce the high populations to tolerable levels for many growers.
“Effective management will rely on a suite of tools,” said Baldwin.
The 15-page publication is available for free download at https://anrcatalog.ucanr.edu/Details.aspx?itemNo=8688.
- Author: Ben Faber
Burrowing Rodents: Developing a
Management Plan
for Organic Agriculture in CA
RELATED ITEMS
- California ground squirrels Otospermophilus spp.
- Pocket Gophers Thomomys spp.
- Meadow voles Microtus spp.
This free publication is available by download.
This publication is best viewed using the free Adobe® Acrobat® Reader. You can download a free copy of the Acrobat Reader from Adobe Systems Incorporated.
- Author: Pamela Kan-Rice
Burrowing rodents can cause extensive and expensive damage to orchards and crop fields. To manage the pests without chemicals used on conventional farms, organic growers can consult a new publication from UC Agriculture and Natural Resources scientists.
“Burrowing Rodents: Developing a Management Plan for Organic Agriculture in California” outlines management within organically acceptable methods using an integrated pest management approach.
California ground squirrels, pocket gophers and meadow voles are the three most common species that cause damage. Squirrels chew on seedlings, fruit and nuts, killing young trees and reducing crop yields. In addition to plants, ground squirrels, pocket gophers and voles can chew on irrigation lines, and their burrow systems can channel water away from plants and erode the soil. The holes and mounds created by burrowing rodents pose hazards to farmworkers and farm machinery.
Meadow mouse or vole that can girdle a tree if you aren't watching
This publication helps growers identify the rodent species on their properties, their life cycles and tools available to control them.
“Growers can read about how to effectively select and set a range of traps for burrowing rodents,” said co-author Margaret Lloyd, UC Cooperative Extension small farms advisor for the Capitol Corridor. “Traps are an important tool for organic management, but maximizing control comes from integrating knowledge. Here we present information about rodent biology, trap efficacy, biocontrol, habitat management, plant protection and other approaches to collectively manage the pest problem.”
In the publication, Lloyd and Roger Baldwin, UC Cooperative Extension wildlife specialist in the UC Davis Department of Wildlife, Fish and Conservation Biology, review the effectiveness of commercially available traps – where to place the traps, whether to use attractants, and methods of euthanizing the animals.
They also offer cultural techniques for deterring rodents such as flooding fields and deep ripping soil to destroy burrow systems. Crops for orchard floors or cover cropping can be selected and managed to minimize habitat that protects and encourages gophers and voles.
For biological control, they suggest barn owls, raptors and snakes might be able to assist, but warn growers that predators alone will not be able to eat enough of the rodents to reduce the high populations to tolerable levels for many growers.
“Effective management will rely on a suite of tools,” said Baldwin.
The 15-page publication is available for free download at https://anrcatalog.ucanr.edu/Details.aspx?itemNo=8688.
- Author: Ben Faber
Even though it's been a mild winter; other than fire, rain and some cool nights, we did have a few days of hot weather, which is just what sets off citrus dry root rot. It pops up after the first hot weather of the spring, and there it was driving down the road. There's nothing that can be done with this tree. Tree removal and replacement is the answer. Prevention is the solution. We know that Fusarium fungus is usually associated with the collapse, but wounding is the key. Mechanical injury from weed whips, discs, gophers, voles, rabbits. Wounding from salt damage might do it too.
Dry root rot, a disease caused by the soil fungus Fusarium solani, has a long history of hindering production of citrus in California. Fusarium solani is a weak pathogen that infects only when there is some kind of stress in citrus tree. However, presence in almost all citrus orchards everywhere in the world including California, enhance its quick exploitation of such stresses. Some of the factors that are possible stress include invasion by other pathogens, such as Phytophthora and Citrus Tristeza Virus (CTV). Other stresses are wounding by gophers/rodents or insects, girdling, asphyxiation especially drowning the tree with too much water, soil nutrient content and fertilization, irrigation, and other cultural practices in the orchard. The pathogen is an opportunist on citrus. With the stress, Fusarium solani begins infection by colonizing the cortical tissue of feeder roots, advances into the lower tap root and/or scaffold root, and move up through the bud union into the center of the trunk. Studies over the years have shown that many rootstocks are susceptible and old trees as well as young twigs are not spared of the disease.
http://ipm.ucanr.edu/PMG/r107100211.html
http://ucanr.edu/blogs/blogcore/postdetail.cfm?postnum=17821
Photo: collapsed tree near and older one on the right, but also near a younger one that probably was a replacement for one that had collapsed several years prior
- Author: Ben Faber
Problem: There was a Valencia farmer in Ojai, farming on a rocky loam. More rocky than loam, on a 10 % slope, where he had been spraying the weeds down, the soil had gradually washed away and all he had left was scattered cobbles.
Solution: He planted a winter cover crop to protect the soil from erosion. He weed whipped it three times a year because that's all he could afford.
Result: After two years he had stopped the erosion, and there was actually a little duff layer forming in the orchard from the decomposing ground cover.
Problem: But now that wonderful cover crop and the cover it provided had attracted gophers that were chewing on the trees and because of inattention had killed a few of them. He couldn't trap fast enough.
Solution: He brought in a ‘Jack Russell' terrier that did a marvelous job at keeping the beasts down.
Problem: About the same time he noticed that he was getting gobs of snails that were getting into the trees. Even though he had lifted the skirts and painted copper on the trunks, they were still getting into the trees. He couldn't keep up with the winter weeds.
Solution: He brought in weeder geese to help with the ground cover and chickens to help with the snails and they worked.
Problem: Now the terrier is distracted by the fowl and is killing the chicks and goslings, as well as the gophers. In fact, he would prefer chasing the fowlings to going after gophers.
Solution: He tied a tether ball around the terrier's neck which slowed it down enough so that the young ones could get away.
Problem: Also with the introduction of birds, he also brought in coyotes which killed the larger birds.
Solution: He brought in a ‘Queensland Heeler' which is a bred that is noted for killing dingos in Australia. They are short-legged, barrel chested dogs that roll over on their back and pretend to be dead and when the coyote comes sniffing around, it grabs the coyote's neck and kills it.
Problem: What's next in this cause and effect chain of events?
This is a true story, but in today's world because of Food Safety and Good Agricultural Practices Certification would not happen with all these animals in the orchard, but something like it happens every time we overturn the flow of events. This is not the only scenario that is played out in agriculture. But hey, that's what a good grower is doing, managing a somewhat chaotic chain of events.