“Invasive insects, diseases and plant seeds can move on cut Christmas trees and other holiday greenery,” said Janice Alexander, UC Cooperative Extension forest health educator in Marin County. “These pests can escape out into backyards and neighboring forests to begin new populations, upsetting the balance of our native ecosystems. Proper purchasing and disposal of holiday greenery helps reduce that risk.”
Alexander recommends taking advantage of local tree recycling programs.
“You should not try to burn the wood indoors as fresh sap can create fire hazards,” she added, “and don't set the tree out in a backyard brush pile where pests and weed seeds could escape onto your property.”
“The most worrisome pests that might be traveling on Christmas trees or greenery this year include P. ramorum, pine shoot beetle and gypsy moth,” Alexander said.
The movement of some fresh trees is regulated. For example, Douglas fir trees are regulated because they are hosts for Phytophthora ramorum, which causes sudden oak death. The disease has killed millions of tanoak trees and several oak tree species in forests throughout California since the mid-1990s.
Pine shoot beetles, Tomicus piniperda, feed on shoots, stunting the growth of pine trees. Large populations of the insects can kill apparently healthy trees.
Gypsy moth, Lymantria dispar, attacks forests and landscape trees, including manzanita, western hemlock, Douglas fir and live oak. Gypsy moth caterpillars feed on hundreds of plant species and are capable of defoliating trees at an alarming rate. A single gypsy moth caterpillar can eat up to one square foot of leaves per day, according to the California Department of Food and Agriculture.
For more information about sudden oak death and forest health, visit Alexander's website at http://cemarin.ucanr.edu/Programs/Custom_Program816. More information about holiday greenery pests can be found at the USDA APHIS website and the Don't Move Firewood website http://www.dontmovefirewood.org/HolidayGreenery.
Mushrooms are popping up all over California thanks to the wet rainy weather we have had across the state recently. They seem to magically appear overnight, like umbrellas on a sunny beach day. This fascinating occurrence doesn't actually happen overnight as it may seem, but they appear once moisture becomes available. Mushrooms expand rapidly by absorbing water from the surrounding soil and consequently ‘pop' out of the ground.
Mushrooms are the fruiting body of a fungus and come in myriad shapes, sizes and colors. They are typically the only part of a fungus that can be seen because the mass of the organism is located underground.
There are approximately 14,000 different classified species of mushrooms, here are a few of my favorites:
The next time you see mushrooms, consider what might be happening underground in your soil. For more information on mushrooms including identification and management, visit UC IPM online.
Enjoy the wet weather and the next time you find yourself excited over a new fungal find, here is a jingle to celebrate the season:
Let it Rain (sung to the tune of ‘Let it Snow')
by Ann King Filmer
Oh the weather outside is fungal
It's like a mushroom jungle
But since we've got much to gain
Let it rain! Let it rain! Let it rain!
deregulated by USDA in November.
“In general, a reduced lignin trait in alfalfa is very welcome,” said Dan Putnam, UC Cooperative Extension specialist in the Department of Plant Sciences at UC Davis. “The low-lignin trait has some interesting potential implications for dairy cows and other ruminants, as well as for yield, agronomic efficiency, and even energy and water use efficiency.”
The new variety, called KK179, was developed by Forage Genetics International, Monsanto and the Nobel Foundation. Some of the field testing took place at UC Davis and the UC Intermountain Research and Extension Center in Tulelake, Calif.
KK179 differs from most other GMO agricultural crops in that the modification improves the plant quality. Other common modifications, such as glyphosate resistance and addition of a Bt gene, were designed to help with pest control.
Another difference is the source of the modified gene, Putnam said. In glyphosate-resistant (Roundup Ready) alfalfa, for example, the plant was modified by inserting a bacteria gene. Gene segments reducing lignin were derived from alfalfa itself.
Lignin is a fibrous part of cell walls in plants. It strengthens stems, helping the plant grow upright. However, its concentration in alfalfa is high compared to other forages, a drawback for what is considered the premiere forage of dairy cows.
“Farmers often try to cut early to reduce lignin,” Putnam said. “Unfortunately, yields are decreased by early cutting, often by many tons per acre. If growers were able to harvest later and still obtain good quality, yields would improve.”
That leads to the potential energy- and water-conserving aspects of the KK179 alfalfa.
“If growers reduce harvests by one each year and increase yields with no quality penalty, energy use would decline,” Putnam said. “Also, the amount of milk produced per unit of water used to grow the feed may be increased.”
KK179 won't be for everybody, Putnam cautions. Some export markets reject GMO technology, so growers should check whether their markets will accept alfalfa with the low-lignin trait. Another concern is the possibility of gene flow for farmers who grow alfalfa seed for organic production or export.
“Further research and experience by farmers and researchers are needed to fully understand the importance and implications of reduced-lignin alfalfa on farms,” Putnam said, “but this trait holds some very exciting possibilities.”
An initiative to enhance competitive and sustainable food systems is part of the UC Division of Agriculture and Natural Resources Strategic Vision 2025
The primary goal of PLT is to teach people how to think, not what to think, about complex environmental issues. This has been the vision of PLT since the mid-1970s, inspiring educators to teach and students to learn about their environment, by doing.
At the outdoor workshops, foresters demonstrate forest practices and talk about forest science. For example, Mike De Lasaux, UC Cooperative Extension forestry advisor in Plumas and Sierras counties, leads participants out to take tree measurements and shows them how foresters determine the age of a tree by taking a core sample and counting the rings.
“The program is designed for teachers and other educators, parents and community leaders who work with youth from preschool age up through grade 12,” said Sandy Derby, UC Cooperative Extension statewide coordinator.
Recognized as a leader in environmental education for more than 35 years, the program started by the American Forest Foundation enhances critical thinking, problem-solving and effective decision-making skills, Derby said.
How does it all work? Project Learning Tree collaborates with a network of more than 200 facilitators, natural resources professionals and researchers across the state to provide three types of trainings: educator workshops, training with the Forest Institute for Teachers and train-the-trainer workshops.
Project Learning Tree's educator workshops are six to eight hours on one or more days and offered at UC ANR Research and Extension Centers located around the state. They focus on introducing the goals and vision of teaching and learning using PLT best practices. Each educator receives a PLT guide for use in the classroom.
After taking the PLT educator workshops, graduates can take a two-day training to learn how to train others. Train-the-trainer workshops are offered a few times each year in different locations.
Project Learning Tree in California was delivered by CALFIRE for 25 years before becoming part of UC Cooperative Extension. In 2013, under UCCE advisor De Lasaux's guidance, Project Learning Tree was brought into UC Cooperative Extension to create more collaborative partnerships, engage more natural resources professionals and to expand the number of educators trained to use PLT materials.
For more information about Project Learning Tree, updates on workshops, or questions on how to become part of this expansive network, contact Sandy Derby at firstname.lastname@example.org or visit http://ucanr.edu/sites/PLT_UCCE. To learn more about the Forest Institute for Teachers, visit http://www.forestryinstitute.org.
For 100 years, the University of California Cooperative Extension researchers and educators have been drawing on local expertise to conduct agricultural, environmental, economic, youth development and nutrition research that helps California thrive. UC Cooperative Extension is part of the University of California's systemwide Division of Agriculture and Natural Resources. Learn more at ucanr.edu.
Some research plantings of Nordmann fir at Washington State University and one Washington farmer's field have been invaded by an adelgid that appears to be closely related to silver fir woolly adelgids, a common pest on Nordmann fir in Europe. Adelgids (pronounced uh-DEL-gids) are certain types of aphids that feed on conifers.
“Fortunately, adelgids attacking Nordmann fir haven't been reported in California, but we want our growers to be aware of them and to let me know if they see symptoms on Nordmann or Turkish fir,” Wunderlich said.
White, cottony masses on tree branches and twisted, curled and discolored needles are signs of adelgid infestation.
In California, growers produce Christmas trees valued at about $6 million per year, according to the USDA's National Agricultural Statistics Service.
Nordmann fir has become a popular species for Christmas tree growers in the Sierra foothills. Native of the Caucasus in Turkey and the Republic of Georgia, Nordmanns have rich color, excellent structure, good needle retention and strong branches for ornament display. Still more advantageous is their resistance to pests and diseases that plague other popular tree species, like white and red fir.
“Because of Nordmann fir, we've been able to plant Christmas trees in areas where we could not grow white fir due to Phytophthora,” Wunderlich said. “Consumers are realizing they like it and are asking for the species.”
If the adelgid makes its way to California, Wunderlich is prepared to work with local growers to devise a control strategy based on the results of research her Cooperative Extension counterparts in Washington are conducting on the pest.
California Christmas tree farmers who suspect their trees have been infested with the silver fir woolly adelgid are encouraged to contact Wunderlich at (530) 621-5505, email@example.com.
An initiative to maintain and enhance sustainable natural ecosystems security is part of the UC Division of Agriculture and Natural Resources Strategic Vision 2025.