White grubs are the larvae of several species of scarab beetles. They are weird, kind of alien-looking little creatures that curl up into a C-shape when disturbed. They tend to grow to around 1-inch long, but some species can get much larger.
I have three raised beds in my garden area and replant them every spring and fall.
For the last couple of years, I have found an unusually large population of what I believe is a kind of grub called Cyclocphala, or masked chafers. The larvae have brown heads and legs and have dark stripes across their backs. The adults (beetles) are golden-brown and have an almost armor-like, shiny coating on them.
“It is not possible to identify these grubs without looking closely at features such as mouthparts and small hairs (called setae) located on their bodies,” said Karey Windbiel-Rojas, with the University of California Statewide Integrated Pest Management Program.
“However, they are the larvae of scarab beetles, and based on where you found them, they could be masked chafers, green fruit beetles, or something similar. What they are very likely NOT are Japanese beetle larvae, since those are more or less non-existent in California.”
Handpicking grubs from raised beds (as I do) and containers can be all the control needed. I have had no noticeable plant damage in my beds.
If you or a neighbor have chickens, they absolutely love grubs and will be overjoyed to help you cut down the population.
Grubs can, however, do major damage to turfgrass. Most damage occurs during late summer or early fall. You will see patches of brown, drying lawn in the infested areas.
Additional damage is often done by moles, voles, birds or skunks that are digging in the grass to feed on the grubs.
Before taking any control measures, dig around the root level of the grass to confirm that in fact the damage is caused by grubs. If you find more than six grubs per square foot, you may want to take action.
Since grubs feed close to the surface, aerating the soil can kill significant numbers of them.
Nematodes (tiny, microscopic roundworms) can also be applied to control grubs. They should be applied when the grubs are young and not overpopulated.
It is best to do so in late summer or early fall. A second application is highly recommended. Be sure to do your research about the proper way to prepare and apply nematodes for grub control.
If these natural measures don't work, it is important to know what kind of grub (or any other kind of pest) you have before deciding to use chemical control.
Get advice about the right chemical to use and the right amount necessary to get the job done. A wrong decision can mean wiping out other species.
You can take a grub (or another pest) specimen into your local Master Gardener office to get information about what to do.
by UC Master Gardener Rebecca Jepsen
This article first appeared in the May 19, 2019 issue of the San Jose Mercury News.
This is the time of year you might spot the beautiful, majestic dance of the honeybees
Most swarming activity takes place from April through May. Bees don't swarm during the rain, so this year we will most likely see the time frame pushed back a few weeks.
Honey bees, Apis mellifera, swarm for one of two reasons. Either the hive has become too crowded so they split into two groups (or more), with one group remaining in the existing hive. Or they abscond. In this case, all bees including the queen abandon the existing hive completely due to lack of food or water, parasite or disease infestation, frequent disturbance by humans or animals, weather changes, poor ventilation, or problems with the queen.
Western honey bees aren't nearly as likely to abscond as African honey bees, (a hybrid of South American and European bees known as Africanized honey bees), which tend to swarm more and be a bit more defensive as well.
Worker bees are able to detect when it's time to swarm due to overcrowding of the hive or the lack of pheromone production from the queen. In preparation for the swarm, the workers will deprive the queen of food in order to slim her down so she can fly. They will also agitate and run her around in order to prevent her from laying many eggs. If they are going to swarm, they will create new queen cells and allow the queen to lay eggs so a new queen can emerge and take over the hive.
Besides making honey, honey bees are essential for pollinating approximately 90 percent of our crops globally. Many of our favorite foods like almonds, most of our cherries, apples, blueberries, and other fruit and nut crops wouldn't exist without these hard-working bees.
According to Deb Conway with GirlzWurk in Saratoga, “Honey bees aren't usually a problem, as they normally set up their hives in tree cavities, shrubs, light poles, or abandoned buildings. However, they can become a nuisance when they take up residence in the walls of your home, garden shed or in your water meter.”
That's when it's time to call someone like Deb who can come and rescue the hive.
Last year was a particularly bad year for honey bees. Some beekeepers reported up to a 90 percent loss in their hives in 2018. Causes for this include varroa mite infestations, increased pathogens due to the warm weather, increased use of pesticides, and a decrease in diversity of food sources.
So, what can we do about a swarm? “If you leave the bees alone, they will leave you alone.,” said Dr. Elina L. Niño, a honey bee expert at UC Davis. “It only takes a few hours, or at most a day or two, for them to find and settle into their new home.”
Bees, as well as our other important and beneficial insects, are struggling. Our tendency to develop land and our extensive use of harmful chemicals are wiping out their natural habitat.
The public can truly make a difference by ceasing to use pesticides and by planting an array of beautiful, attractant plants such as ceanothus, lavender, echium, rosemary, penstemon and mint (mint is only recommended in containers because it is so invasive). For more bee-friendly plant ideas, visit UC Davis Häagen-Dazs Honey Bee Haven.
Let's all commit to creating safe and nurturing spaces in our backyards, gardens (and yes, even on those balconies and decks) where our much-needed pollinators and beneficial insects can not only survive, but thrive!
For help in relocating a swarm or hive, or to contact a local beekeeper, visit the Santa Clara Valley Beekeepers Guild, which has information about Santa Clara as well as surrounding counties.
by UC Master Gardener Rebecca Jepsen
This article first appeared in the April 16, 2019 issue of the San Jose Mercury News./h3>
Tomatoes and pepper and herbs, oh my! Markets and tours will soon be popping up all around the Bay Area
The 25th annual Spring Garden Market brought to you by the Santa Clara Master Gardeners, will take place on April 13th, 9 a.m. to 2 p.m. in Martial Cottle Park, 5283 Snell Ave, San Jose. This year's event is being held in conjunction with the Park's Spring Celebration, which runs from 10 a.m. to 3 p.m.
The market is a fabulous, fun-filled, family event featuring tasty food, music, plant sales, gardening talks and tours throughout the day.
If you enjoy edible gardening or would like to learn, this truly is the event for you. Among the plants for sale will be 77 varieties of tomatoes from cherry and plum to classic and beefsteak, and 72 choices of peppers, from super sweet to fire-engine hot varieties.
If you haven't grown your own herb garden, we will have everything you need to get you growing. Growing herbs is a great project to start with your kids. Choose from 10 varieties of basil, and add in some chives, dill, oregano, fennel, lemongrass, even some chocolate mint.
This year our flower team has outdone themselves by seeding up more than 50 varieties of amaranth, celosia, cosmos, rudbeckia, salvia, sunflower, zinnia, and many other blooming beauties.
And, of course, we will have an amazing array of succulents. You can purchase individual plants to make your own creations or buy one of the gorgeous, pre-planted “works-of-art” that our succulent team has put together.
There will also be a number of educational talks on many topics such as container gardening, tomatoes, chiles and peppers, and how to grow succulents and native plants. Workshops will include how to care for and clean your garden tools, composting, controlling gophers and moles, and much, much more.
For more information visit the Master Gardener's website.
The Going Native Garden Tour 2019, now in its 17th year, will feature tours of more than 100 gardens from Morgan Hill to San Mateo showcasing California native plants. The North Bay tour is on May 4 and the South Bay tour is on May 5. Both run from 10 a.m. to 4 p.m. Visit the website for more information.
The Bringing Back the Natives Garden Tour will feature more than 30 native/Mediterranean gardens throughout Alameda and Contra Costa counties. The15th annual tour takes place May 5, 10 a.m. to 5 p.m. Some gardens will feature live music, artwork, native plants for sale and plenty of activities for the kids. Visit the website for more information.
The 10th annual Spring Garden Market of San Mateo and San Francisco counties, a plant sale and educational fair brought by the UCCE Master Gardeners of San Mateo and San Francisco Counties, is April 13, 9 a.m. to 1 p.m., San Mateo Events Center, 2495 South Delaware St., San Mateo. Visit the website for more information.
The 8th Annual Great Tomato Plant Sale will take place in three East Bay locations. Note that only cash or checks are accepted. Visit the website for more information.
- Central County Sale: Our Garden 2405 Shadelands Dr., Walnut Creek, March 30, 10: a.m. to 3 p.m.
- West County Sale: Richmond Public Library, 325 Civic Center Plaza, Richmond, April 6, 10 a.m. to 3 p.m.
- East County Sale: Mangini Garden in the Contra Costa County Fairgrounds, 1201 W 10th St, Antioch.
by UC Master Gardener Rebecca Jepsen
This article first appeared in the March 14, 2019 issue of the San Jose Mercury News.
The best prevention is to be sure your trees are healthy and happy
Woodpeckers are part of the Picidae family that also includes piculets, wrynecks, flickers, and sapsuckers. They are found in most of the world except for Australia, New Zealand, Madagascar, and extreme polar regions. We have 17 species here in California.
They can range in length from just under 3 inches to nearly 20 inches and can be fairly drab in color (olive and brown) to vividly bold (bright red, black, white and gold). They have short, strong legs, and most species have four toes, two of which face backward, making it exceedingly easy to climb and grasp onto tree trunks and limbs.
Although it may seem that a persistent woodpecker is killing your tree, the opposite is generally true. Woodpeckers actually feed on insects that have invaded the bark of an already distressed tree.
Woodpeckers are attracted to wood-boring beetles, termites, carpenter ants, caterpillars, and spiders. However, they will also eat nuts, fruit, bird eggs, lizards and small rodents.
They prefer wood that is already dead for their foraging and nest building. Since most trees have some amount of dead wood, these birds are usually not considered harmful. When they detect insects within decaying wood, they use their strong beaks to make small holes and then extract the prey using their extremely long, barbed tongues.
Sapsuckers, as the name implies, prefer to feast on tree sap and the insects that are attracted to tree sap. These birds are known to voraciously attack trees, causing serious damage and sometimes death to the tree. They are migratory birds and can wreak havoc on entire groves of trees throughout the United States. According to the U.S. Forest Service, sapsuckers cause mortality rates in 67 percent of gray birch, 51 percent of paper birch, 40 percent of red maples, 3 percent of red spruce, and 1 percent of the hemlock that they attack.
They frequently return to the same trees year after year. They increase the size of their holes, looking for more sap and inflicting more and more damage. As the tree declines, bacteria and fungus can take hold, amplifying the damage and increasing the likelihood of tree mortality.
Sapsuckers usually make tiny holes in a horizontal pattern around the tree, while woodpeckers mostly make large, random holes. Most damage is caused during their breeding season that runs from February to June.
All woodpeckers are protected under the Migratory Bird Treaty Act of 1918, and some are listed as endangered species.
So what can you do to protect your trees?
Wrap burlap or hardware cloth around the areas of the tree that have been attacked. There are also repellents such as Tanglefoot Bird Repellent that will help fend off the noisemakers. However, when deterred, they will usually seek out another tree. If they are attacking an already sick tree, one you are not particularly fond of or one that is not in the best location, it may be best to just let them peck in peace!
The best preventative measure is to regularly inspect your trees for signs of infestation. Termites and carpenter ants love to feast on wood, and trees are a good source. So, if you see an invading pest, deal with it right away.
First and foremost, determine what type of pest you have and then use an eco-friendly, organic method of control. When using any pesticide, (organic or conventional) it is important to determine exactly which type of pest you are trying to kill and use only the recommended dose. More is definitely NOT more, and if you aren't careful, you can wipe out an entire ecosystem of beneficial insects and species.
by UC Master Gardener Rebecca Jepsen
This article first appeared in the February 17, 2019 print issue of the San Jose Mercury News.
It's a good idea to know about our local fungi, especially if you have children or pets
Mushrooms are actually the spore-bearing, fruiting bodies of fungi. They pop out of the ground in order to spread their spores for reproduction. They have an underground network of threadlike cells called mycelium that can live for many years, often growing in mulched areas, compost piles or on decaying tree bark and roots.
Mushrooms are a highly sought-after delicacy around the world. But don't start picking them and bringing them into your kitchen without knowing what you're doing. In fact, never consume a mushroom you find unless you are 100 percent certain what it is or have had it properly identified by a qualified professional. I've listed some resources below.
Mushrooms come in all shapes and sizes. Some mushrooms have caps (curved tops) with gills (feathery membranes) or pores (small holes) underneath. The caps are usually supported by stipes (stems/stalks). Others have rings and cups. Some varieties have stems that rise from a cup (also called the volva). In order to properly identify some mushrooms, a “spore print” and molecular identification is often required, said Hung Doan of the UC Davis Department of Plant Pathology.
One of the most common mushrooms here is the turkey tail (Trametes versicolor), which can be found nearly anywhere you find decomposing stumps, logs or old wood. Their clustered, fan-shaped masses have contrasting shades of brown to reddish-brown, and their caps are velvety and slightly fuzzy.
Another common species found in our area is the Armillaria (often called honey fungus), one of the largest living organisms in the world. It is a parasitic fungus that feeds on living and dead plant material. Their yellowish-brown caps can be convex or conical and are generally moist and sticky to the touch.
One specimen of the species, Armillaria solidipes, found in Oregon, is said to be 2,400 years old, and covers more than 3.4 square miles!
Although thought to be rare here in California. I found what appears to be Boletus erythropus in my own backyard. Since the mushroom is not fresh, proper identification can be difficult. Doan said it is likely one of two species — Suillellus amygdalinus (formerly Boletus amygdalinus) or Boletus erythropus.
Its unusual and varied color really caught my eye. The large caps vary from dark to light brown or even coppery bronze. The pores start out orange and then become bright red to rusty brown. The spore tubes are lemon-yellow but turn bluish-green when cut or bruised. They can be found under spruce and beech trees, and occasionally under oaks, as this one was.
Several varieties of mushrooms are toxic, but very few are actually deadly. One of the most deadly found here in the Bay Area is the Amanita phalloides, Death Cap, which has rings and cups as described above. It accounts for nearly 50 percent of all deaths caused by mushrooms. Symptoms of toxicity include severe cramping, vomiting, diarrhea and stomach pain. It can cause liver and kidney damage, and as the name implies, often death.
Its large, spore-less cap can be 2-6 inches wide and can range in color from pale yellow to olive-green. The cap is covered by a thin white veil. Stems and gills are usually white and have a ring and cup (you may have to dig into the soil to see them). It is often mistaken for the edible Paddy Straw mushroom (Volvariella volvacea), which has pinkish-brown gills.
Death Caps are generally found when out hiking and or foraging in our coastal hills where coast live oak and cork trees are found but can be found in urban areas as well.
There are edible varieties of Amanita, but avoid them unless you are a skilled and experienced “shroomer”.
There are many mycologists (those who study fungi) right here in the Bay Area. To learn more, or to join an upcoming foraging adventure, check out these organizations:
- Bay Area Mycological Society (BAMS)
- Mycological Society of San Francisco (MSSF)
- Sonoma County Mycological Association (SOMA)
by UC Master Gardener Rebecca Jepsen
This article first appeared in the January 27, 2019 issue of the San Jose Mercury News.