Procrastination is rarely one's friend, but never is this truer than when dealing with weeds. Some gardeners say, breezily, that a weed is simply a plant in the wrong place. I say that it is something that you didn't plant and don't want. (I shall ignore the lemon balm that I planted and have allowed to rampage over my yard for several years. At least the birds like it.)
Do your weeding now. The weeds haven't yet flowered or set seeds, and they are easily removed from the soft, yielding soil, which is still damp from rain.
If you remove weeds at this immature stage, you can chop them up and put them in your compost pile. If you wait until they have seeds, you'll need to put in your yard-waste bin that goes to the municipal compost site. Most home composters don't have a pile that gets hot enough to kill weed seeds. You don't want viable seeds in your compost, obviously.
The best tools for weeding are gloves (to avoid contact dermatitis from some weeds), a narrow trowel, a garden fork and either a thick pad for kneeling or a gardening seat. A Japanese-style gardening knife is handy, too.
The idea is not to disturb the soil too much. Weed seeds live deep in the soil, but they only get enough heat to sprout in the top few inches of soil. I did not know this, which is why my vigorous dandelion removal project with lots of shovel work resulted in even more dandelions the next year. Now I use a gardening knife for dandelion removal.
We need to remove weeds because they compete with other plants for water and nutrients. They can also harbor pests and pathogens. Some people are allergic to certain weeds, too.
But not all weeds are bad. For years, people dug clover out of their lawns or used herbicides to remove it. However, clover is fragrant, requires less care and fewer chemicals than a lawn, and bees love it. Gardening styles are changing, and clover is a welcome sight to many home gardeners.
According to the University of California Master Gardener Handbook, weeds have some redeeming value. They reduce soil erosion, provide cover and nutrition for creatures such as birds and a nectar source for honeybees, create habitat for beneficial insects, and improve the soil when they rot. Many are edible and may even be a source of pharmaceuticals. My backyard is full of wild onion right now, and I plan to make a mushroom onion soup with them.
Even with these virtues you probably don't want bindweed or vetch or spurge all over your yard. The first step in smart weed eradication is identification. If you go to the UC Master Gardeners of Napa County website, click on Gardening Resources. Next, go to Garden Pests and Diseases and, finally, to Weeds. This link can help you determine the identity of the invasive plant you want to remove. It also tells you the best ways to eradicate the weed. UC Master Gardeners advocate environmentally friendly methods of weed removal, so get out your garden gloves.
Some weeds can be lifted out of the soil gently, roots and all. Others require a more determined effort with a narrow spade, trowel, or gardening knife. Careful hoeing works, too.
Some people allow weed seeds to sprout, then remove the sprouts. Weeds are so adapted to their environments that they are usually the first things to come up, as I have learned. You can also cover weeds with mulch to prevent them from growing, but they need to be completely covered.
Even wild fennel and mustard, those quintessential Napa Valley plants, are considered weeds by some. Yet they are also edible, and they attract pollinators. You can let the pollinators enjoy them so long as you remove them before they produce seeds.
Whatever you decide, starting your weeding program now is better than waiting until it's hot, the ground is bone-hard, and the weeds are flowering. Like Alice in Wonderland, I am good at giving advice, but erratic at following it; however, this weekend I will work on the weeds.
Food Growing Forum: Join UC Master Gardeners of Napa County for a seminar on “Winter Seed Starting and Planning” on Sunday, February 12, from 3 pm to 4 pm via Zoom. Learn about selecting spring seeds, seasonal timelines for crops, succession planting, soil preparation, special supplies, and tips for success. Register to receive the Zoom link: http://ucanr.edu/2023FoodForumFeb
Workshop: Join UC Master Gardeners of Napa County for a workshop on “Spring Garden Planning for Warm Weather” on Saturday, February 25, from 10 am to noon, at Las Flores Community Center, 4300 Linda Vista Avenue, Napa. Learn how to prepare your landscape for warmer weather, including cleanup, pruning, tool care, soil preparation and seed starting. The workshop will be indoors, with some outdoor activities if weather permits. Registration required: https://surveys.ucanr.edu/survey.cfm?surveynumber=39854
Library Talk: Join UC Master Gardeners of Napa County and Napa County Library for a free talk on “Success with Citrus Large and Small” on Thursday, March 2, from 7 pm to 8 pm via Zoom. Learn how to choose the best tree for your space, plus healthy growing techniques, fertilizing, managing pests, watering, protecting from frost and growing in containers. Register to receive the Zoom link: https://ucanr.edu/2023MarCitrusLibraryTalk
- Author: Kathy Keatley Garvey
Her seminar also will be virtual. The Zoom link:
https://ucdavis.zoom.us/j/95882849672
"Infectious disease prevalence is among the top five drivers of global extinction, including in wild bees," the bee biologist says in her abstract. "With the global decline of wild bees, our work aims to contribute to understanding how community characteristics shape infectious disease prevalence in plant-pollinator communities. Infectious parasites can influence host immunity, physiology, and reproduction. The sharing of floral resources is a common mode of disease transmission among pollinators."
"Increasing host aggregation on floral resources can increase disease prevalence, that is, amplification," Ponisio noted. "Conversely, high host species diversity---even if accompanied by host aggregation---may dilute infection. Because bees pick up parasites from flowers, but not all flowers transmit parasites equally, flower abundance and diversity may further contribute to parasite dilution. In three systems, mass-blooming sunflower in Yolo County, CA, harvested forests in Coast Range, OR, and high elevation meadows across the Southwestern U.S., I examine how the factors that shape plant-pollinator abundance and diversity and the ramifications for parasite prevalence in wild bee communities. Across all systems, more than 40% of bees have at one parasite. Both natural (phenology) and human-induced (years post-harvest, mass-blooming crops) modification of the bee and floral communities indirectly affected parasitism by altering host community characteristics. I found a consistent amplification effect of host (bee) abundance and detected dilution through either host diversity or floral diversity in each system."
On her website, Ponisio elaborates: "We focus on understanding the mechanisms by which species interactions maintain species diversity, and how we can harness these processes to manage and restore diversity in human-modified systems. We focus on pollinators because they are critical for pollination in managed and natural plant communities, but our research is broadly applicable across ecological interactions. Our aim to discover new insights into how communities form, evolve, and persist through time and space, aiding in the prediction and prevention of community collapse. We combine modeling, synthesis and field-based work, and adhere to the principles of reproducible, open science."
Lauren, who grew up in Fresno, holds a bachelor's degree in biology, with honors, in ecology and evolution (2010) from Stanford University, and her master's degree in biology (2011) from Stanford. She received her doctorate from the Department of Environmental Science Policy and Management, UC Berkeley, in 2016.
She conducted postdoctoral research at UC Berkeley and served on the faculty at UC Riverside before accepting her current position. She received graduate fellowships from the National Science Foundation and the National Institute for Food and Agriculture, as well as a postdoctoral fellowship from the Berkeley Institute for Data Science. She was named among the Global Food Initiative's “30 Under 30” in Food Systems in 2016.
Ponisio says one of her most difficult field work experiences occurred in Yosemite National Park, according to her People Behind the Science podcast. "Their study on the effects of fires on pollinators required them to backpack out to remote sites where there had been natural fires. Lauren started working months ahead of time to get ready for the trip and prepare dehydrated meals for the lab to eat. One day, they opened the large canister where they had been storing their food to protect it from bears, and they discovered the food was gone. All that was left was a handwritten note from someone thanking them for leaving out food."
"The next day, the lab's field assistant tripped over a log and sprained her ankle. Then they accidentally left their sampling gear at a site and had to hike all the way back to retrieve it. Later, a bear came into their campsite and destroyed many of the traps they needed to collect pollinators for their study. At this point, Lauren and her colleagues were exhausted, surviving on snacks, their field assistant could barely walk, and much of the equipment they needed had been destroyed. In the face of all of these challenges, Lauren stayed calm. These kinds of things happen in field research, and everyone made it back to share the story."
Ponisio was featured on National Public Radio's "All Things Considered" in January of 2021 when she discussed "Wildfires Open Forests for Wildlife and Research."
Ponisio is the lead author of a recently submitted journal paper, "Mass-Flowering Crops Attract Bees, Amplifying Parasitism," co-authored by G. P. Smith, H. Sardinas, J. Zorn, Q. S. McFrederick and S. H.Woodard. (See CV)
The UC Davis Department of Entomology and Nematology's winter seminars are held on Wednesdays at 4:10 p.m. in 122 Briggs Hall. All are virtual. They are coordinated by urban landscape entomologist Emily Meineke, assistant professor. (See schedule.) She may be reached at ekmeineke@ucdavis.edu for technical issues.
