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Videos show hikers how to avoid Black Friday stampedes on park trails

In a new series of videos, a cow puppet provides advice for hikers from UC Cooperative Extension on sharing open space with livestock.

While Americans traditionally beat a path to the malls the day after Thanksgiving, many opt out of shopping on Black Friday to enjoy the outdoors. In regional parks and other open spaces, hikers may encounter crowds of a different sort – cattle grazing with their calves. A 1,200-pound cow blocking the path can be daunting.

With a little patience and understanding, people who hike, bike and horseback ride can coexist peacefully with the cattle, according to Sheila Barry, UC Cooperative Extension livestock and natural resources advisor in Santa Clara County.

For happier trails, UC Agriculture and Natural Resources has produced a series of videos that show hikers how they can amicably share open space with their beefy neighbors. In a two-minute video, a black cow puppet with a furry white face describes how to politely coax cows to moo-ove aside without spurring a Black Friday stampede.

“We wanted to produce videos that are entertaining as well as informative,” Barry said. 

The cow pun-filled video also describes the ecosystem services cattle provide by consuming nearly their body weight in plants. By grazing, cows manage the vegetation, reducing wildfire fuel, increasing water capture and promoting the diversity of native grasses and wildflowers.

In “Sharing open spaces with livestock,” the UC Agriculture and Natural Resources livestock experts give four simple tips for safely sharing open space with cows on the trail: 

  1. Keep moo-ving and speak in a normal tone. Sudden movements and loud noises may surprise cows.
  2. Approach cows from the side or front. They find it udderly unnerving to have someone sneak up from behind, the bovine blind spot.
  3. Steer clear of getting between a protective mother and her calf.
  4. If you need to move a cow, step slowly into its flight zone. Invading the animal's “personal space” will motivate it to mosey aside.

A second video, “Sharing open spaces with livestock when you have a dog,” gives advice for dog owners to keep their best friends safe around cows.

In a third video, “A year in the life of a cow,” the UC Cooperative Extension spokespuppet describes a typical year for a beef cow.

“The videos are a fun way to educate the public about grazing on rangelands,” said Stephanie Larson, UC Cooperative Extension livestock and rangeland advisor in Sonoma County.

The videos are based on the UC ANR publication “Understanding Working Rangelands,” authored by Barry and Larson, at http://ucanr.edu/shareopenspace.

Watch all three videos on UC ANR's YouTube channel:

Sharing open spaces with livestock https://youtu.be/Qd8LEGLDhaM

Sharing open spaces with livestock when you have a dog https://youtu.be/zzdGnfFwmcA

A year in the life of a cow https://youtu.be/znJbWknVXVg

Posted on Friday, November 17, 2017 at 8:48 AM

Barn owls help clean up rodents naturally

Barn owl adult, photo by G. Rohman, grohman@gmail.com

The screech of a barn owl at night may be startling or annoying to some. But others may find their harsh calls satisfying, knowing that barn owls are out, feeding on pesky rodents.

They're fierce hunters with a voracious appetite for mice, voles, gophers, and rats. A family of five barn owls, including two adults and three young will feed on about 1,000 rodents during a season. When they nest twice in a year, that number doubles and you wind up with some good help on rodent control that's safe and free.

So, the next time you hear that eerie, rasping sound at night, don't panic. Instead, think about all the good the owls are doing. Even better, invite a family of barn owls to your property by building a nest box for them and creating a home.

Identifying barn owls. If you're lucky to spot one in an old barn where they're often found (hence their name), they have iconic white heart-shaped faces, white chests, and tan-colored backs with spots. Barn owls are nocturnal and can be recognized by their drawn-out rasping screech. Unlike other owls, they don't hoot. They often shriek when they leave their roost to hunt and make hissing and snapping sounds when startled.

Barn owls have excellent vision and hearing for finding prey in the dark and capturing it with their sharp talons and beaks. They're quiet hunters, flying close to their prey without being heard, due to specialized feathers, making them incredibly good predators. Barn owls are found world-wide and occupy a wide range of habitats, including natural, agricultural, and urban areas, but prefer to hunt in more open areas as opposed to forests. They readily hunt rodent pests in grape vineyards, alfalfa fields, and along levees, making them valuable allies for farmers.

How do you attract barn owls? Barn owls are cavity nesters, including cliffs, trees, and buildings such as barns, so they will readily use nest boxes. Plans for how to build nest boxes can be found in the UC Agriculture and Natural Resources (UC ANR) booklet, Songbird, bat, and owl boxes. This handy guide also shows how to attract insectivorous birds and bats to help control insect pests naturally.  Barn owl boxes and plans can be found online or through local sources, such as G. Rohman (photographer). Barn owls begin nesting in February, so now is the time to put up a house before males and females select nest sites. Boxes should be mounted 10 feet off the ground on metal poles to prevent mammal predators from accessing the boxes and feeding on eggs or chicks.

Paint the boxes white to keep them cooler and help prevent weathering and face them northeast. Add some timothy hay for bedding (often sold in small bags in stores for rabbit feed). Wooden nest boxes are generally preferred over plastic ones. Fifty gallon drums can also be used; just remove the top, retaining a lip so the chicks don't fall out, add some hay, and hoist it up on a rafter in a barn and secure it well with a chain. Avoid disturbing nest boxes during the breeding season (February through August), as barn owls will often abandon nests if disturbed while nesting. 

Barn owl house on a pole. (Photo: G. Rohman)

Who moves into the nest box? A family of barn owls. Females generally lay four to seven eggs from February to April, which hatch in about 30 days. While they incubate the eggs, the males bring food to the nest. The baby owls fledge in about 10 weeks, but stay around the nest until fall, when they wander off, usually within 30 miles of where they were born. Sometimes a second clutch of eggs is laid in May. Barn owls do not migrate, so tend to stay in an area year-round and will reoccupy a nest box the following year. They generally forage about one to three miles from their roosts. They are only mildly territorial in that they will defend their nests if you get too close. This means that you can put up several nest boxes in an area and expect occupancy from several families. Barn owls generally only live for about two years. Great horned owls are the fiercest predator of adult barn owls (and collisions with cars).

Barn owl bringing prey back to the nest box. (Photo: G. Rohman)

What are they eating? The favored prey of barn owls is rodents, including voles and gophers. Like other owls, they often swallow their prey whole and then undigested bones and fur are coughed up (regurgitated) as owl pellets. These pellets can be dissected and prey readily identified by the skeletons left behind. Farmers appreciate owls and other raptors because they feed on rodents that can damage their crops and irrigation systems (Wildlife Survey).

UC ANR researchers, including Roger Baldwin, UC Cooperative Extension vertebrate pest control specialist, are currently evaluating the economic impact of barn owls for rodent control in agricultural lands. It is important to note that rodents reproduce rapidly so barn owls cannot always keep up with rodent outbreaks and other methods of control might be needed to prevent crop damage (Rodent Control). But, every rodent a barn owl takes is one less we have to deal with!

How about maintenance? Barn owl boxes need to be cared for and cleaned once a year during fall or winter (October to December) as the pellets can quickly fill up a nest box. Doors for accessing the inside of the boxes need to be secured, hinges lubricated, and mounting structures checked during annual inspections. Avoid breathing unhealthy dust when cleaning the house and always make sure no one is home. Although this takes time, the pellets cleaned out might have added value. A Yolo County farmer mentioned he has a buyer for his pellets, which are used for science projects where students dissect them to learn about skeletons and barn owl diets. He read his recent owl pellet invoice noting, “The pellets are graded from small at 10 cents each to premium at 20 cents each and I sold over 100. Barn owls are great!”

Barn owl pellets. (Photo: Chuck Ingels)
 
Barn owl with a gopher on a nest box. (Photo: G. Rohman)
Posted on Monday, November 13, 2017 at 8:36 AM
Tags: barn owls (1), nest boxes (1), rodents (1)

Digging Deep: Exploring the diversity of soils in the Sacramento Valley

Participants gather around the first soil pit of the field tour, as Toby O'Geen provides a brief natural history of the land.

Not more than three months on the job and Konrad Mathesius is hard at work bringing farmers together to discuss the unique challenges that Sacramento Valley farmers face. As the new UCCE agronomy advisor for Sacramento, Solano and Yolo counties, his role is designed specifically to help growers with their crop issues – pests, disease and fertility – but with a strong background in soil science, Mathesius hopes to shed light on the diversity of soils in the region and the unique management considerations that each necessitates.

In hopes of highlighting this diversity of soils and encouraging growers to dig a little deeper to better inform their management practices, Konrad enlisted the help of UCCE soil resource specialist Toby O'Geen to lead a field tour of three major soils in the southern Sacramento Valley. The event included three pit stops on two Yolo County farms and brought out a diversity of participants from USDA Natural Resources Conservation Service agents, to resource conservationists, to farmers and crop advisors.

Kicking things off at Rominger Brother's Ranch -- a diversified family farm in Winters that grows everything from wine grapes to processing tomatoes to rice, wheat, corn, onions, alfalfa and hay -- O'Geen took the audience on a journey back in time, describing the rich natural history of the former floodplain that has given rise to the rich, productive soils that support California agriculture today. After introducing himself as a pedologist, or a scientist who studies the nature and properties of soil, he went on to introduce the five soil forming factors and their role in molding initial (1) parent material (i.e. rocks), under the influence of (2) climate, (3) topography and (4) organisms and over a given period of (5) time into soils. 

Yolo County farmers and UC Cooperative Extension specialist Toby O'Geen, right,peer deep into the processes that formed the land just beneath their feet.

Proving that soil scientists take the term “pit stop” literally, Mathesius shifted the conversation to a 1.5-meter deep hole in the ground, dug out the day before with a back hoe. Step by step, he walked participants through the process of analyzing a soil pit – cleaning the face, identifying horizons or individual layers and using the senses to assess soil properties and determine function. As he struck the face of the pit with a rock hammer, an audible difference was detected between the surface layers and the subsurface. 

Working backwards from the sound, he explained that the subsurface was significantly harder, which he attributed to a finer texture and ultimately identified as a clay pan, a restrictive layer that prevents roots from penetrating deeply and has the capacity to waterlog soils, due to poor drainage. O'Geen offered some tangible advice as to how to manage these soils, quipping that a deep rip would be no better than cutting butter with a knife (eventually it all just settles back into place) while likening a slip plow to a giant shank that just inverts the soil, mixing things to about a depth of 6 feet and permanently eliminating the problem.

UCCE agronomy advisor Konrad Mathesius, left, talks soil texture and water-holding capacity.

From there, Mathesius segued into a hands-on exercise to determine the soil texture, or percent distribution of various size particles, allowing participants to work on their pottery skills making balls and ribbons with the clay-rich soils.  Discussing the many functions that soil texture controls, led the conversation down a rabbit-hole around water holding capacity and how to calculate the range of plant available water for your soil.

With the demos out of the way, they voyaged to the next pre-dug pit, bringing participants face to face with the harsh reality of soil heterogeneity. Just 300 feet away and it was as if we had ventured into another environment altogether, yet these soils formed in the same place, under the same climate and similar vegetation, but in a completely different time with slightly different starting material.

By changing just a couple of the ingredients in the special sauce of soil formation the results are completely different featuring a clay dominant surface soil and entirely different water management challenges. And these aren't just any clays, but a special class that swell and shrink as they wet and dry, oftentimes shearing roots under the pressure and creating a hospitable environment for disease to thrive.  O'Geen suggested trying to keep them in the sweet spot where they are consistently moist, but not wet, and never allowed to dry out. Unfortunately, there is no precise measurement to that formula, “you just have to be almost like an artist. It's a lot of feel to it and the numbers sometimes just don't work out. It just comes with years of experience. Its one of those native intelligence things that you just have to feel your way through,” he noted.

Up close and personal with a soil pit, showing participants how to use basic tools of observation to assess soils!

Caravanning 20 miles back towards Davis, the tour arrived at the third and final pit, located at Triad Farms, a tomato operation in Dixon. Well-drained, young and fertile, Yolo loam soils are the poster children of agriculture, owing in large part to regular deposits of silts from past flood events. With not many management challenges to speak of, conversation immediately shifted towards an undocumented challenge that farmers on the eastern side of the Sacramento Valley are all too familiar with – the unavailability of potassium, even under intensive fertilization regimes. While the jury is still out on the cause and while it contradicts what soil scientists expect to find in those regions, possible explanations were tossed around and O'Geen used the opportunity to stress the importance of speaking up about things growers or advisors see going on in their area. Turns out the USDA-NRCS is working on updating its inventory of soil surveys, documenting soils across the nation and is currently seeking input on what's working for growers and where things are differing on the ground.

Ultimately, in closing, Mathesius called for more engagement between the university, extension and growers. O'Geen reminded everyone that “You can really learn a lot by digging a hole, looking at stuff, and developing theories.  Sometimes you're wrong, but they're kind of fun to talk about."

Posted on Monday, October 30, 2017 at 3:03 PM
Tags: geology (2), Konrad Mathesius (1), soils (1), Toby O''Geen (1), Water (17)

Cannabis crop expansion into forests threatens wildlife habitat

This series of satellite images shows the development of a greenhouse complex in a Humboldt County forest.

Planting cannabis for commercial production in remote locations is creating forest fragmentation, stream modification, soil erosion and landslides. Without land-use policies to limit its environmental footprint, the impacts of cannabis farming could get worse, according to a new study published in the November issue of Frontiers in Ecology and the Environment.

“Despite its small current footprint, the boom in cannabis agriculture poses a significant threat to our environment,” said co-author Van Butsic a UC Cooperative Extension specialist in UC Agriculture and Natural Resources and the UC Berkeley Department of Environmental Science, Policy and Management. “To mitigate the anticipated environmental impacts, now is the time for policymakers and land-use planners to set regulations to manage the spatial pattern of cannabis expansion before crop production becomes established.”

Earlier studies have shown that cannabis production causes environmental damage, including rodenticide poisoning of forest mammals and dewatering of streams due to improper irrigation.

Cannabis grows near a salmon stream Humboldt. Diverting water to irrigate cannabis can dewater streams during the summer and impact wildlife.

Cannabis, as either a medicinal or recreational drug, is now legal in more than 30 U.S. states and in several countries. In California, where medicinal marijuana has been legal since 1996, voters in November approved the sale and possession of one ounce of marijuana for recreational use. As a result, cannabis production is ramping up.

Effective policymaking for a new crop can be challenging without scientific data. In this study, Butsic and Ian J. Wang, assistant professor in the Department of Environmental Science, Policy and Management at UC Berkeley, and Jacob C. Brenner, associate professor in the Department of Environmental Studies and Sciences at Ithaca College in New York, present an approach for early assessment of landscape changes resulting from new agricultural activities. 

Their approach uses per-unit-area analysis of landscape change. To study forest fragmentation in northern California, the scientists compared the effects of cannabis cultivation to those of timber harvest from 2000 to 2013 in Humboldt County.  

Based on the size, shape and placement of the cannabis grows among 62 randomly selected watersheds, they quantified the impacts relative to those of timber harvest.

Satellite image A shows a clearing with greenhouses (upper left in clearing) and rows of cannabis plants (lower right in clearing), surrounded by a buffer area. Image B shows a typical pattern of large areas of clear‐cuts for timber harvest and various stages of regrowth.

“We found that although timber has greater landscape impacts overall, cannabis causes far greater changes in key metrics on a per-unit-area basis,” Butsic said. 

On a per-unit-area basis, the cannabis grows resulted in 1.5 times more forest loss and 2.5 times greater fragmentation of the landscape, breaking up large, contiguous forest into smaller patches and reducing wildlife habitat.

“The results show how important it is to consider environmental impacts at different scales,” Brenner said.

Current California law caps the size of outdoor cannabis production to 1 acre per parcel, to prohibit the development of industrial-scale cannabis operations outdoors. An unintended consequence of this law may be small dispersed cannabis grows that edge out wildlife.

While the long-term effects of cannabis cultivation on the environment are unknown, the researchers concluded that land management and agricultural policy informed by further research may reduce these threats in California and in other states and countries where cannabis production can be regulated.

“Studies like this one have the potential to directly inform local land-use policy and state environmental regulation,” Brenner said. “It's exciting to be a part of this research because it is capturing a human-environment phenomenon at the moment of its emergence.” 

 

 

Posted on Monday, October 30, 2017 at 3:03 PM
Tags: cannabis (1), Van Butsic (1)

Replanting the Sierra Nevada after an ecological catastrophe

Given California's changing climate, should Sierra Nevada residents replant pine trees after so many died during the 2010-2016 drought? The short answer is yes, says Susie Kocher, UC Cooperative Extension forestry advisor.

“We have every reason to believe that pines will continue to be an important part of mixed conifer forests in the Sierras,” Kocher said.

Dead trees can be seen in the foreground and on the distant mountain side. (Click on photos for higher resolution.)

Kocher spoke at a meeting for UC Master Gardeners, volunteers who provide landscape advice to the public in California. Questions have been coming in to Master Gardener hotlines from mountain residents wondering what to do after unprecedented tree loses in the last few years.

Most California forests are suffering from severe overcrowding due to 100 years of aggressive fire suppression and selective harvesting of the largest and most resilient trees. They were then subjected to five years of drought.

“There were just too many stems in the ground,” Kocher said. “The drought was very warm, so trees needed more water, but got less. These were optimal conditions for bark beetles.”

Western pine beetle is a native pest that attacks larger ponderosa pine and Coulter pine trees weakened by disease, fire, injury or water stress. Bark beetles are tree species specific, so other beetles target other species of trees in California's mixed conifer forests. Typically, bark beetles bore through tree bark and create long winding tunnels in the phloem. An aggregating pheromone attracts additional bark beetles to the tree, and heavily attacked trees invariably die.

Healthy pine trees can fight off bark beetle attack by secreting pitch. Trees weakened by drought are unable to fend off an attack. In this photo, a pine beetle is stuck in pitch that oozed from the tree.
 
Evidence of bark beetle attack are exit holes on the outside, left, and winding galleries under the bark.

During the drought, 102 million Sierra Nevada trees died from bark beetle attack or simply lack of water; 68 million of those died in 2016 alone. But after the abundant rainfall in the 2016-17 season, the bark beetle population seems to have crashed.

Landowners with 20 acres or more may be eligible for a state cost-sharing program to remove trees, reduce the fire hazard and replant new seedlings. Landowners in mountain communities who wish to revitalize their properties can contact local UC Master Gardeners for recovery advice.

UC Master Gardeners are plant enthusiasts who have passed an intense training program presented by UC academics. They participate in continuing education annually to update and maintain their knowledge. More than 60 Master Gardeners from Mariposa, Madera and Fresno counties gathered in Oakhurst in October to learn from UC scientists how to work with mountain homeowners whose towering trees have died. Similar training sessions, all funded by a grant from UC Agriculture and Natural Resources, were held in El Dorado and Tuolumne counties in June.

UCCE specialist Jodi Axelson points out bark beetle damage.

“There is life after beetles,” said Jodi Axelson, UC Cooperative Extension forestry specialist at UC Berkeley.

“Eco systems are stretched, and then they come back,” she said. “You must remember the time scale of forest change is long and pines have been a major species in the Sierra Nevada for at least 28,000 years. As long as there have been pines, there have been bark beetles.”

The scientists suggest that people who own forestland take a step back and assess the landscape after their dead trees have been removed.

“We're seeing a lot of young cedar and white fir surviving the drought. Oaks seem to be doing really well,” Kocher said.

She suggests landowners thin young trees so available sun and soil moisture are focused on the healthiest trees. Water seedlings that are receiving more sun than before to reduce stress. Planting native conifers is the best option. Due to climate change, she recommends choosing trees from a slightly lower elevation to hedge against warmer temperatures in the future.

Pines are adapted to the California forest, but may need help to regenerate. When the ground is moist in the late fall or spring, plant seedlings 10 to 14 feet apart. New trees should be planted well away from homes to maintain defensible space and at least 10 feet from power lines.

“Please don't set them up for future torture,” Kocher said. “That's just sad.”

UCCE forestry advisor Susie Kocher, center, speaks during a field trip to a forest where many trees were killed by bark beetles.

To help the new trees become established, cover the ground around the tree, but not touching the bark, with two or three inches of mulch and irrigate weekly during the dry season for the first few years.

Questions about special circumstances may be directed to local UC Master Gardeners. Find the local program here: http://mg.ucanr.edu/FindUs/

Pouch fungus is evidence of a bark beetle kill. The beetles carry fungus into the cambial layer of the tree on their bodies. On recently killed trees, small white conks, the fungus' fruiting body, issues from bark beetle tunnels.
 
UC Master Gardeners learn from experts about replanting conifer forests.
 
Posted on Wednesday, October 25, 2017 at 1:13 PM

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