Tuesday, December 30, 2014

Happy New Year, Mr. Freeze!

It took awhile, but several hours of continuous freezing temperatures are finally coming to Sacramento's 2014-2015 wintertime experience...on New Year's morning. The National Weather Service is forecasting a freeze watch for a wide swath of Northern California from New Year's Eve through January 2. Their prediction includes temperatures falling into the mid to upper 20's for eight or more hours during the night and early morning hours. "A FREEZE WATCH MEANS SUB-FREEZING TEMPERATURES ARE POSSIBLE. THESE CONDITIONS COULD KILL CROPS AND OTHER SENSITIVE VEGETATION," warns the National Weather Service. 

Further down the Central Valley, the Fresno and Bakersfield areas - prime citrus growing regions - are facing even more dire predictions of extended cold this week with temperatures predicted to dip to 21 degrees Thursday and Friday mornings. That's the classic definition of a hard freeze,  deadly to plants, livestock, pets and water pipes.
Freeze Protection for Lemon Tree
 
Frozen Hosta
















 

 

  Many of us learned to take hard freeze warnings seriously in 1990, when consecutive low morning temperatures of 22, 18, 21 and 23 in Sacramento descended upon us during the period of December 21-24. Temperatures did not get above 25 degrees in parts of the San Joaquin Valley for three to five days and all time record low temperatures were set at Sacramento, Stockton, and Bakersfield. Many records were set for duration of freezing temperatures. The agricultural industry was devastated as acres of trees, not just fruit, were destroyed. Thirty-three counties were disaster-declared.

Homeowners back then learned which plants don't like it cold (hibiscus, geraniums and other plants popular in the Bay Area and Southern California); and, which plants were the hardy survivors (another reason the oleander was chosen for the Highway 99 median strip).
The National Weather Service has a nifty Tabular Forecast chart link within their "Additional Forecasts and Information" list at the bottom of their local forecast page. This tabular chart predicts the temperature, hour by hour, for the selected location, for the next six days. This is probably more useful for predicting the duration of freezing temperatures, rather than the actual temperatures themselves. When those durations exceed four hours at temperatures of 28 degrees or less, that's when plant damage can become fatal to sensitive plants. Remember to pinpoint your own location when using the local forecast page link by using the Google map embedded on that page to find your location.
Here's a last minute checklist for your home and garden if the TV weather people (or panicky bloggers) tell you upcoming morning low temperatures will be in the mid-20's:
 
• If it hasn't rained, water plants thoroughly, especially container plants.

 
• If possible, move sensitive container plants next to a south or west facing wall.

 
• Cover citrus and other sensitive plants with burlap, row cover fabric or sheets (be sure to keep the sheets dry). Tent plastic sheets on supports over the plants; don't let plastic touch plant leaves. A light bulb placed in such a plant can offer a few degrees of protection. For best protection, sheets should reach all the way to the ground around citrus trees and other freeze-susceptible plants.

 
• If using an anti-transpirant polymer coating material such as Wilt-Pruf or Cloud Cover, apply at the warmest time of the day, or at least six hours before an expected frost. Read and follow all label directions. If using these products, thoroughly water the plant before applying. In my opinion, use these coatings only as a last resort. Watering plants, moving plants or covering/adding heat to sensitive plants is a more effective strategy.

 
• Disconnect hoses and drip lines, removing end caps. Lay out straight, off the driveway and out of the path of vehicles. If possible, turn off any exterior water lines at the main; or, thoroughly wrap any exposed pipes and faucets.

  • To prevent broken grass blades, don't walk on a frozen lawn.
 
• Remove the lowest sprinkler head on each line for drainage.



Protect exposed pipes around wells and pumps
  







  • To prevent frozen attic pipes, let lukewarm water trickle out of the indoor faucet farthest from the inlet. Also, let faucets with pipes running along an outer, north facing wall trickle during the night.  
 
 
• Open cabinet doors to get more heat to the pipes. Close the garage door if water pipes pass through the garage.
 
• Setting your thermostat nightly at 55 can add needed heat to the attic pipes.

 
• If leaving the house for a vacation during an expected freeze, turn off the water to the house, and open up the faucet farthest from the inlet. Be sure to turn off your water heater.

  • Cover unprotected faucets and pipes, including any spa or pool equipment.
 
• To prevent cracking tile, run your pool and spa equipment during the freezing hours. 

 
• Don't forget about your pets during a prolonged freeze. Bring them indoors at night. Move or replace their drinking water. Break up any frozen water in bird baths. 


 




• Cover the worm bin, too! Or, move it indoors.

Thursday, December 11, 2014

Trees and Storms




 



40-50 mph winds + several inches of rain over a few hours = the recipe for a typical winter storm in much of California. 







 

TV news crews rush to the most photogenic damage during these rare occasions: downed trees, usually leaning against a house or crushing a car.


Without the correct care of the trees on your property, winter storms and trees will not get along. Most susceptible are the trees that keep their leaves year round, such as eucalyptus and camphor, along with the conifer family: pines, firs, redwoods and cedars. All that mass of greenery acts as a sail in a heavy wind, bending trees at ridiculous angles. Another cause of winter tree failure is crown rot, which despite its name, refers to the deterioration of the root system near the base of the tree. Combine that with a couple of inches of rain onto already saturated soils, and you have tree roots heaving towards the surface, leading to these pictures popping up on the TV news:

   

If this is the view from your window, the day after a major rain and wind storm is not necessarily the best day for the gardener to tackle the hazardous task of cleaning up the remnants of trees, shrubs and other plants that took a beating. If wind and rain is still in the forecast, the prevalence of slippery conditions and the chance of more falling debris should limit your cleaning chores to dragging broken branches away from the scene of the crime. It is not a good day to be climbing ladders or scrambling into trees while balancing a chain saw. Leave that to the professionals.

     
Arborists offer this good piece of advice for those surveying the fallen aftermath of a major storm: Limb failure is largely a product of poor tree maintenance over time. Take care of your trees, or they may take care of themselves in ways you won't appreciate.
     
According to the University of California publication, "Inspect Your Landscape Trees for Hazards", a nice day in autumn (or winter, spring or summer, for that matter) is the time to take an inventory of any possible future tree damage before you, your house or your car becomes the next victim of a falling tree or branch.



Leaning Trees: Are your trees not as upright as the result of recent heavy winds? Can you see newly upheaved roots or soil around those trees? Then, immediate action is required: call in a professional, certified, bonded and insured arborist to do an onsite inspection and offer a solution (find one near you at treesaregood.org). Newly leaning trees are an imminent hazard. 
If you have a tree that has leaned for a number of years, that tree can still be a hazard during wet, windy weather. Taking periodic photographs can help you determine if a greater lean is developing.

 
Multiple Trunked Trees: This co-dominant condition can result in breakage of major tree parts during storms. Usually, these trunks are weakly attached. Inspect the point where the two trunks meet; if you see splitting beginning, call in an arborist.

 
Weakly Attached Branches: Trees with many branches arising from the same point on the trunk are prone to breaking during wind storms. Prune out any split branches. Thin out multiple branches.


 
Hanging or Broken Branches: If you see storm damaged branches hanging from the tree, remove them as soon as possible. This includes removing any completely broken branches that may be resting elsewhere in the tree's canopy.



Cracks in Trunks and Branches: Measure the depth of any cracks with a ruler. If those cracks are more than three inches deep, call in an arborist to determine the best course of action.

 
Dead Branches/Trees: Branches or entire trees that have completely died are very likely to come tumbling down in a storm. Dead branches are most noticeable in the summer when the tree is in full leaf.


Cavities and Decay: Large, open pockets where branches meet the trunk, or at the base of the trunk, can mean big trouble. The presence of mushrooms on the bark or on exposed roots may indicate wood decay. Call in an arborist.



The Arbor Day Foundation website has this animated guide to proper pruning techniques.



Also: Tips for Hiring an Arborist. 

And, an illustrated guide for pruning large branches (which are branches that are greater than the thickness of your thumb): the three-cut method.



Wednesday, November 12, 2014

How Much Cold Can Your Citrus Trees Handle?

We are entering the shivering season for the Central Valley, Bay Area and low foothills. Late November through mid-February is the most critical time here for protecting frost-susceptible plants.


Frost Cloths Protecting Lemons, Mandarins, Oranges



This is especially true for citrus tree owners, who are anxiously keeping an eye out on the upcoming weather forecasts.







Several days before an expected frost (temperatures dipping down to 32 degrees) is the time to gather the necessary implements to protect your citrus trees, including giving the ground beneath them a good soaking (moist soil is better than dry soil at moderating the temperature beneath the tree).

Most gardeners first thoughts about protecting their citrus trees during a frost or freeze is, "protect the fruit!"

Four Winds Growers, the Winters-based wholesale grower of many excellent varieties of citrus, offers the Citrus Variety Information Chart at their website, FourWindsGrowers.com

Included in that chart is extensive information about each citrus variety, including suitability for indoor growing; its bloom and fruiting seasons; its recommended summer heat level to produce good fruit; and, its minimum tolerable temperature for preservation of fruit quality.

  The chart points out that lemons, limes and citrons are most sensitive to frost, while sweet oranges, grapefruit, tangerines and calamondins are intermediate. Kumquats and Owari Satsuma Mandarins are the most frost-tolerant, braving temperatures into the twenties (that would classify as a freeze).

From that chart, here are the temperatures (in degrees Fahrenheit) at which citrus fruit damage may occur. 

Sweet Oranges
Washington Navel Orange  28 
Trovita Orange  28 
Cara Cara (Pink) Navel Orange 28 
Lane Late Navel Orange  28 
Robertson Navel Orange  28 
Shamouti Orange (Jaffa Palestine)  28 
Valencia Orange  28 
Midknight Valencia Orange  28  

Blood Oranges
Moro Blood Orange  28 
Sanquinelli Blood Orange  28 
Tarocco Blood Orange  28 
 
Sour Oranges
Bouquet De Fleurs Sour Orange  28 
Chinotto Sour Orange (Myrtle-Leaf)  28 
Seville Sour Orange  28 
Bergamot Sour Orange  32 
 
Mandarins
Gold Nugget Mandarin (Patented)  26 
Tango Mandarin (Patented)  32  
Owari Satsuma Mandarin  24 
Dancy Tangerine  32 
Clementine Mandarin (Algerian)  28 
Murcott Mandarin  32 
California Honey Mandarin  32 
W. Murcott Mandarin  32 
Kinnow Mandarin  32 
Kara Mandarin  32 
Page Mandarin  32 
Piie Mandarin  32 
Kishu Mandarin  32 
 
Lemons
Improved Meyer Lemon  32 
Eureka Lemon  32 
Lisbon Lemon  32 
Ponderosa Lemon  32 
Variegated Pink Lemon  32 
Yen Ben Lemon  32  

Mediterranean Lemons
Villafranca Lemon  32 
Genoa Lemon (Gea)  32 
Limonero Fino Lemon  32 
 
Limettas
Millsweet Acidless Limetta  32 
Marrakech Limetta  32 
 
Limes
Bearss Seedless Lime (TahitiPersian)  30 
Kaffir Lime (KiefferThaiWild)  32 
Meican Lime (Key)  32 
Thornless Meican Lime  32 
Meican Sweet Lime  30 
Palestine Sweet Lime  30 
Rangpur Lime  32 
 
Grapefruits
Oroblanco Grapefruit  32 
Rio Red Grapefruit  28 
Star Ruby Grapefruit  28 
Chandler Pummelo  28 
Cocktail Grapefruit  28 
Chinese Grapefruit  28 
Melogold Grapefruit  28 
 
Kumquats
Meiwa Kumquat  28 
Nagami Kumquat  24 
Indio Mandarinquat  26 
Centennial Variegated Kumquat  30 
Nordmann Seedless Nagami Kumquat  28 
Marumi Kumquat  26 
Eustis Limequat  32 
 
Citrons
Buddha's Hand  Fingered Citron  32 
Etrog Citron (Ethrog)  32 
 
Other Interesting Varieties
Minneola Tangelo  28   
Australian Finger Lime  32   
Yuzu  24   
Calamondin  32  
Variegated Calamondin  32

But what about the overall health of the citrus tree? How low can temperatures go during a freeze event before the tree is toast? 

 "I consider 22 degrees to be terminal for citrus tree cambium cells," says Cedar Seeger of Four Winds Growers. The cambium layer is the growing part of the tree, the cells that are producing new wood and healing wounds. It is located just beneath the bark.

And that's for a citrus tree in tip-top shape: good health, with moist soil around it during a freeze. Cedar uses the example of a Meyer lemon tree:


Blanket + Tomato Cage for Citrus Protection
"We often have a two to three hour dip to 28 degrees after storms; and if the above conditions are met, even Meyer lemon trees can survive, albeit not to happily, without protection. 28 degrees for four hours probably won't kill the tree, provided the rootstock cambium doesn't freeze. It will defoliate and lose twigs. At 24 degrees things start to get dicey. That's when the blanket, frost cloth, bonnet and/or the old-style, large outdoor Christmas lights that give off some heat will work wonders. Remember, those blankets and bonnets need to go to the ground in all cases."






Chandler Pummelo, Pummeled by 2010 Freeze



You may recall Thanksgiving Week of 2010, when morning low temperatures dipped well below freezing for six days in a row, led by a citrus-killing 27 degree morning on Thanksgiving.








When a large, cold-air mass moves in from the north after a storm in the winter, that is called an advective freeze. The one that sticks out in most gardeners' memories here was the freeze of mid-December 1990, when nighttime temperatures fell into the teens for several days in a row, with a couple of days that didn't climb above 32 degrees. To add even more injury, a second cold snap hit near the end of the month, with temperatures dipping into the mid-20's. Many of the most susceptible (frost intolerant) landscapes were completely lost; some nurseries never recovered.

"Our first year in the citrus business here in Winters was 1990-91. My wife, Mary Helen, and I have a Masters in Disaster," says Cedar Seeger. 

Which is why Cedar is an adherent of watching the dew point, the temperature at which saturation has been reached, when water vapor condenses into water. The lower the dew point, the more danger of cold damage to your plants. One good online source for dew point temperatures is the National Weather Service's Tabular Forecast Page  , which offers a forecast for two days in advance (that link is for Sacramento). 

"A good watering going into an advection night is mandatory. If the ground and surrounding grass is wet, it creates a micro dew point environment around the trees. In a dry, cold La Nina winter such as we're about to get, it is important to remember the dew point concept. At 22 and below, it's full on emergency response, pile straw, hay around trunks, anything, lights, covering," says Cedar, a man who learned these lessons the hard way.  But he is not an adherent of running sprinklers during a freeze.

"My experience with overhead sprinklers is that they more often than not freeze up, and then it's all over. And you are risking branch breakage on that ice-entombed citrus. Yeah, it can work, but screw it; it's messy, risky and a lot of work. Use the large Christmas lights and mid-weight frost covers. But pay attention to the trunk / rootstock. If that freezes, it's a goner."


Citrus trees most at risk to fatal damage from a frost or freeze are the young trees. It is vital that they be covered completely when a heavy frost or freeze is predicted, and provide protection for the trunk, bud union and rootstock area. That can include trunk wraps, newspapers, old carpeting. If possible, move small containerized citrus closer to the house, preferably next to a south or west-facing wall to maximize reflected heat.

Monday, September 1, 2014

Every Season is Ant Season

When it gets hot, the ants start marching indoors. When it rains, in come the ants. Too cold? The ants know where its nice and cozy: your kitchen, bathroom and pet food bowls. Outdoors, the pet food bowls and garbage cans are also ant attractants. Argentine ants, those busy little black ants, are in march formation year round.

 
In years past, we would reach for the spray can and douse those little scavengers. But not anymore.

 Many of those spray pesticides are only effective with direct contact on the ants. And the stronger sprays, with residual action to thwart the next wave of ants, is potentially harmful to you, your kids, your pets.



So, here is what we are doing now: following the recommendations of the UC Davis Integrated Pest Management Project for Ant Control.

That includes:

• Determine what the ants are attracted to and remove the food source
• Vacuum trails, wipe them with soapy water, or spray with window cleaner
• Locate entry points and caulk openings or plug with petroleum jelly
• Put out bait stations with liquid ant bait or apply gel bait at entry points
• Baits take time to work so continue to clean up trails
• Indoor sprays are not usually necessary.

• Avoid products packaged as granules that contain the active ingredients cyfluthrin or permethrin. Although these products may be mistaken for baits, they are actually contact insecticides that rapidly kill foragers and do not control the colony.




Before wiping up (or wiping out) the little critters, follow their trail. Note their entry point into the house. Seal it up. We have found ants entering the house in a variety of small avenues: beneath moulding, cracks in the window frame, behind electrical outlet plates...and one of the ants' favorite entries: that large holes beneath the sink where the pipes enter the house.



According to the UCD IPM page on ant control, "If ants can be thoroughly washed away and excluded from an area, an insecticide is probably not necessary. Vacuuming up ant trails or sponging or mopping them with soapy water may be as effective as an insecticide spray in temporarily removing foraging ants in a building because it removes the ant’s scent trail, especially if thorough cleaning is done at the entry points. Some soap products such as window cleaners can kill ants on contact but leave no residual toxicity. Certain plant-based oils are also applied for this purpose, but their odor can be offensive."

Oh, and another lesson we learned the hard way: if you put those ant baits indoors, you will attract more ants inside. Look for ants crawling along the outside of the house, and place the baits there, being sure to follow all label directions.



What about those ant sprays that are intended to be used as a perimeter spray along the outside of the house? Stick with the bait traps, says the UCD IPM page: "Spraying around the foundation will not provide long-term control because it kills only foraging ants without killing the colony. Perimeter treatments may appear to knock down the population, but ants will quickly build back up and invade again. To try to achieve long-term control, some pest control companies offer monthly perimeter spray programs. Perimeter treatments pose more risk of environmental upset than baits in bait stations and are less effective than a bait-based IPM program."



Ant baits are not ant traps, even though some ants may be stuck there. The whole point of ant baits: they get the stuff on them, take it back to their nest, where they share it with others...and then croak. Be patient. It may take a week or so for the baits to work on the ant nest.





More info about ant baits from the UCD IPM project: "Baits are insecticides mixed with materials that attract worker ants looking for food. They are a key tool for managing ants and the only type of insecticide recommended in most situations.  Ants are attracted to the bait and recruit other workers to it. Workers carry small portions of the bait back to the nest where it is transferred mouth-to-mouth to other workers, larvae, and queens and other reproductive forms to kill the entire colony. Bait products must be slow-acting so that the foraging ants have time to make their way back to the nest and feed other members of the colony before they are killed. When properly used, baits are more effective and safer than sprays."
• Sweet sugar baits such as boric acid (use low concentrations with less than 1% of the active ingredient) are highly attractive to Argentine ants throughout the year.
• Protein baits are attractive to ants in spring when colonies are producing new offspring. (Baits like fipronil or hydramethylnon are effective.)

• Place baits outdoors; avoid indoor baiting as that may attract more ants into the home.

• Place baits near nests, trails, or along foundations, preferably in the shade.

• Baits should be placed in protected areas away from children and pets.

• Offer small portions of each bait to see which one is preferred before employing an extensive baiting program.

• Follow up regularly to make sure bait is working and place fresh bait as necessary.

How baits work:
• Worker ants are attracted to the bait and take it back to the nest where the entire colony, including queens, may be killed.

• Bait must be slow-acting so workers won't be killed before they get back to the nest.

• Results may not be evident for several weeks.

• Bait stations or ant stakes are easiest to use and safest for the environment.
http://www.amazon.com/gp/product/B0016J1MZG/ref=as_li_tl?ie=UTF8&camp=1789&creative=390957&creativeASIN=B0016J1MZG&linkCode=as2&tag=getgrowingwit-20&linkId=REQOA2DBYJUF6FIN


Ant baits contain various active ingredients and attractants. We have tried a variety of different ones, to appease the finickiest of ant diners. Besides the Gourmet liquid ant bait, another one of my favorites is powdered boric acid in a squeeze bottle, another less toxic alternative.

For those that prefer a homemade concoction for ant control, Horticulture professor Debbie Flower of American River College in Sacramento recommends this formula:

1 part boric acid (I use 1 teaspoon) - available at most garden centers
9 or 10 parts sugar (so 9 or 10 teaspoons sugar)
Add enough water to make a slurry.
Put slurry in a small container, tuna can size.
Add 2 or 3 cotton balls and rotate them until they are completely covered in the slurry.
Put a lid on the container.  Lid must have holes big enough for ants to crawl through.  (Lid is not absolutely necessary but it keeps water and dirt out)
Bury in soil so lid is at soil level.
Leave it alone.  You won't see dead ants.  They visit, take the bait back to the colony, and kill the entire colony.


Monday, August 18, 2014

Oak Galls, Bouncy Offspring Return in 2014

Dear Farmer Fred,

"Can you identify the pink and little brown balls growing now on our oak tree? I don't remember seeing these before.
Is it some kind of parasite? If so, what should we do? Thank you. We enjoy your weekly show very much." Margaret of Shingle Springs (CA)

Margaret:
Yep, it's oak gall season in California! Galls are interesting creations of several varieties of (usually harmless) wasps. No action is necessary on your part, except to enjoy the show.

The Integrated Pest Management Project at UC Davis says this about galls: "Most galls are caused by cynipid wasps and gall midge flies. The adult gall wasp is a small, stout, shiny insect with very few wing veins and a purple or black body. Adult gall midges are tiny, delicate flies, often with long, slender antennae. Galls are distorted, sometimes colorful swellings in plant tissue caused by the secretions of certain plant-feeding insects and mites. These unusual growths may be found on leaves, flowers, twigs, or branches. Most galls are not known to harm trees. Prune and dispose of galls if they are annoying. This may provide control of some species if pruning is done when the immature ones are in plant tissue and before the adults begin to emerge."


Retired state entomologist Baldo Villegas chimes in:
"Your picture of a blue oak tree have several types of oak galls made by several species of small, non-stinging wasps in the wasp family "Cynipidae". As an entomologist, we refer to the members of this family as "cynipid wasps". They are unique among the wasps in that they lay their eggs on plant tissue resulting in a distinctive plant gall encasing the egg/larva. Each cynipid wasp species make different and distinctive galls and one can identify them based on the gall type. Obviously, your blue oak sample had several types of galls and therefore several species of wasps. There is not much you can do to control these gall wasps. They are native species that co-evolved with the blue oaks in the area. The wasps are not killing the trees and they also don't appear to weaken them; so, my recommendation is to just let them be."


"1) The most obvious are the "echinid galls" produced by the wasp "Dryophanta echina".  These galls vary from pink to bright red and have the spiny galls.

2) The second gall that you asked for was for the small brown galls that look like little brown balls? These are probably "jumping oak galls" caused by the wasp "Neuroterus saltatorius."

Thanks, Baldo!

Other interesting oak galls:
And here's more fun with jumping oak galls...

  Lynn in Chico writes: "Yesterday I noticed my sidewalk was dancing, sort of.  Looking closer I saw what looked like bird seed scattered, but the seeds were jumping!  I collected a few of the tiny eggs (?) and they are still jumping this morning. They can get about a half inch of air when they jump.  I assume they are some sort of bug getting ready to hatch. Most of them are on the ground under the oaks on my property.  Please let me know if they are good bugs or bad bugs."

     Again, those would be oak galls, not a problem. Here is more info:
Jumping Oak Galls Are Interesting and Harmless to Oak Trees

by Ed Perry,  U.C.  Farm Advisor

"If you have a Valley oak tree growing in your landscape, or if you visit one of our local parks where Valley oak trees are growing, you may notice a strange phenomenon occurring this year. The ground beneath many Valley oaks this year is covered with pinhead-sized yellow or brown seedlike objects, most of which are hopping around. The tiny things are called "jumping oak galls", and are formed by a tiny, dark wasp. The wasp belongs to an interesting family of wasps called the cynipids.

"The galls are actually malformations of plant growth. The tiny gall-forming wasp lays an egg in an oak leaf at a precise moment in the treeĆ­s growth cycle, causing normal plant cells to multiply at an unusually high rate. As a result, the tiny egg becomes encased in the gall composed of oak leaf tissue.

"When the egg hatches, the gall provides both food and a living chamber for the larvae. In summer, the oak gall drops to the ground with the tiny wasp larvae inside. The insect moves in jerks, causing the entire gall to jump around on the ground. ItĆ­s believed that the larvae hop around in an attempt to find a crack in the soil to hide up in. At maturity it transforms into a pupae, and later into an adult which chews its way out of the gall. The wasps themselves are dark colored, so tiny that youĆ­ll probably never see them, and harmless to people.

"A few insect-formed plant galls are found on willow, poplar, rose and other plants, but more than 100 different kinds are found on oaks. The entire oak tree is fair game for the cynipid wasps, which form wasps on leaves, buds, twigs, branches, roots and even the acorns. Each cynipid wasp species forms a gall of particular size, shape and color; no other species forms one quite like it. Also, each one lays its eggs in a specific plant part.

"Besides the jumping oak gall, you be familiar with the common oak apple, a large gall up to three inches in diameter. These large galls are common on the deciduous Valley oaks, and contain one or more tiny cynipid wasp larva inside. You may also find a pink, star shaped gall on the undersides of Valley and blue oaks. Other galls are cone shaped, or round and fuzzy, or shaped like tiny loaves of bread.

"In California, most insect caused galls are not harmful to the plant. In some cases the galls may damage leaves or even cause twigs to die. However, the insect galls cause no serious permanent injury. Because of their complex life cycle, it is very difficult to prevent cynipid wasps from forming galls; in most cases, it is unnecessary to do so." 


Jumping oak galls (video courtesy of listener Darcy):

Monday, August 11, 2014

They're Big, Loud and Hungry: The Green Fruit Beetles Are Back


 While searching for the few remaining pluots in the garden last night, a familiar loud buzz zoomed by my ear. You may be hearing that same ferocious buzzing as you are picking the backyard tomatoes, figs, peaches, pluots, corn and berries these days. You just might be disturbing the eating habits of the green fruit beetle (Cotinis mutabilis), munching away at the overripe and damaged fruits and vegetables in your garden. It's not just the sound that will stop you in your tracks. The combination of the biplane-like buzz as well as the sight of these slow flying, large (an inch and a quarter long), metallic green-shelled creatures might make you drop your crops.

 


 The late Sacramento County Farm Advisor, Chuck Ingels, noted an increased number of calls about this species of beetle (also known as the fig beetle) from concerned gardeners in 2014, especially in southern Sacramento County. But its march up the state is continuing.

 

Retired State entomologist Baldo Villegas says the presence of green fruit beetles in our area has increased dramatically in the last 15 years. Until the late 1990's, they had only migrated as far north as Fresno.
 






"This beetle is now widespread from Mexico to the southwest and into northern California," says Villegas. "They are migrating northward fast." Villegas explains that the beetle is more vexing for backyard gardeners than commercial growers. "I consider them a nuisance pest," says Villegas. "They feed on rotting or open fruit and are attracted to them by the gas emitted by the fruit."

 
A native of Mexico, Villegas recalls the green fruit beetle as a harbinger of summer. "We used to catch them on fruit damaged by birds or in rotting fruit laying around on the ground," says Villegas. "We would tie a piece of string on one of their hind legs and that would allow them to fly along side of us."

 



Green Fruit Beetle Larvae
Unlike a balloon on a string that escapes your grasp, the green fruit beetle is not going to drift away, high into the sky. Right now, those beetles are laying their eggs in your piles of garden compost, manure and mulch. The best control is to remove any such piles from the areas where you have seen the feeding adults. Turning the piles frequently will expose the larval stage of these beetles, a C-shaped, creamy white grub. Hand picking or flooding the area for two days can limit these noisy munchers during the next gardening season. In addition, chickens consider those grubs a delicacy.

To limit the spread of the adult beetles now, take away their food supply: fruit that is getting too soft on the vine. Trapping might be somewhat successful, according to former UC Davis Integrated Pest Management Director Mary Louise Flint. In her excellent book, "Pests of the Garden and Small Farm," she says that the green fruit beetle can be attracted to a half-filled, one-gallon jar, containing a 50-50 mix of peach or grape juice and water. Make a funnel out of small mesh wire and place it in the jar's opening. This will allow the beetles to get inside, but not back out.

Insecticides are not recommended against the adult green fruit beetle. The UC Davis Integrated Pest Management website offers these tips for green fruit beetle control: "Early harvest and removal of fallen fruit can reduce damage. To manage grubs, remove all manure, lawn clippings, or leaf piles from areas near fruit trees and turn compost piles frequently to speed decomposition and expose small grubs."




 


And if the buzzing is too loud? Another good argument for plugging in the headphones and not having to listen to these beetles while gardening.










    



    (Green Fruit Beetle larvae photo
Licensed under Creative Commons Attribution-Share Alike 3.0 via Wikimedia Commons - http://commons.wikimedia.org/wiki/File:PC180002JuneBeetleLarvae_wb.jpg)
    




    




















Friday, July 4, 2014

Starting an Urban Farm? This Site Can Help.

As local food has gained popularity, more city folks are growing food in their own backyards. Now they have a new online resource to consult about urban farming. The University of California Division of Agriculture and Natural Resources has launched a website to provide practical, science-based information for urban agriculture.

At the University of California's Agriculture and Natural Resources' Urban Agricultural website ( http://ucanr.edu/urbanag ) visitors will find information on raising livestock, crop production, marketing and policies for farming in their backyards, on a few acres, at a school or in a community setting.

Rachel Surls, a UC Cooperative Extension advisor in Los Angeles County, and a team including UCCE farm advisors, policy and advocacy experts, urban planners, agricultural economists and others created the new urban agriculture website in response to the results of a UC survey of urban farmers in California.

"Our team interviewed urban farmers around the state about their challenges and successes, and what information they really needed as they got started," said Surls, who specializes in sustainable food systems. "Based on their needs, we looked for science-based educational materials that would be helpful and packaged them into this website.

"The site will be a resource for urban farmers who are selling what they grow, as well as school and community gardeners, and folks who are keeping some backyard chickens and bees.  We also intend it to be a resource for local policy makers who are making decisions that impact farming in California cities." 

Many urban farmers are beginning farmers, according to Surls. "They need basic information on planting, pests and irrigation, as well as information that's more specific to farming in the city," she said. "For example, they must navigate local laws and regulations that impact farming which include zoning and health codes."

The UC ANR Urban Agriculture website also advises urban farmers about environmental issues that they may encounter.

"Urban soils can sometimes be contaminated and may need testing and remediation," Surls said. "Farming close to neighbors in the city can also bring special challenges."

She encourages people to check back for updates as the Urban Ag website continues to grow.

"We'll also share stories about urban farms around California and news around the state about urban agriculture policies and initiatives," Surls said.



(information provided by UCANR)