Monday, April 27, 2015

You’re All Wet if You Don’t Take Almond Disease Management Seriously in a Drought Year

Farmers are quick to tell you that no two years are the same. They come to expect the unexpected. Past performance doesn’t necessary predict future results.

Almonds are well into fruit development at this time.
This certainly is the case with almond growers. Their crop has been doing well so far this season with nuts developing about a month faster than normal.
“Every year is different with the progression of the crop. This year we’re ahead,” says Gurreet Brar, a farm advisor and almond expert with the University of California Cooperative Extension in Fresno County.
As a result, it’s important that almond growers stay on top of monitoring the trees in the orchard and not simply relying on the calendar as a guide. At this stage, almonds are well into fruit development (have you seen the size of some almonds already?)
Moisture build up can lead to diseases in trees.

Brar says growers should be looking this spring and summer for any signs of diseases in the orchards. Post-bloom diseases could linger if there is high amount of moisture in an orchard. For example, microsprinklers may be angled high up toward the canopy and that could cause moisture build-up in the canopy, creating an environment ripe for diseases to spread. Here are some of the things to look for this spring:

Alternaria damage on a leaf.  - UC IPM photos
·        Alternaria: large brown spots form on the leaf. Alternaria develops when there is a lot of humidity or stagnant air. Leaf spots can spread quickly in June and July and can completely defoliate trees by early summer.

Rust damage is evident on leaves.
·        Rust: Rust colored spores appear on leaves and can spread by air movement. It’s a serious problem in orchards near waterways or areas with high humidity in the spring and summer. Leaves can fall prematurely, causing trees to become weak.

Sacb is evident by grayish black spots the nut.
·        Scab: Grayish black spots show up on leaves, fruit and twigs in the late spring or early summer. Usually, the disease thrives during prolonged wet spring weather. As Brar points out, orchards irrigated by sprinklers can get this disease if the water reaches the foliage.

Hull rot causes leaves to wither and die.
·        Hull rot: This disease surfaces several weeks before harvest when leaves wither and die. Fungi will invade hulls and produce a toxin that kills the shoot attached to the fruit. This will impair maturity of other green fruit on the shoot. The fruit will stay on the tree after harvest. 

Brar points out the drought doesn’t have direct affect on almond tree diseases. Indirectly, though, the lack of water will weaken tree health and make them more susceptible to diseases in the future.

Reports of canker are up.
Right now, Brar has been fielding a lot of calls from growers concerned about canker in the stems and lower canopy. Called bacterial canker, this disease becomes evident in the spring and includes limb dieback with rough cankers and amber-colored gum. Also, leaf spots and a blast of young flowers, spurs and shoots can develop.

 UC IPM notes orchards with nitrogen-deficient trees, young trees 2 to 8 years old or high populations of ring nematode are prone to bacterial canker. Prevention is the best way to manage the disease. Here’s what UC IPM recommends:

  •         Maintaining proper nutrition, especially nitrogen.
  •        Applying low-biuret urea before leaf drop can reduce the canker size of infected trees.
  •      Using a nematicide treatment in October can help reduce the disease severity

Monday, April 20, 2015

Summer-like Spring Weather Spurs Plant Growth in Valley

Whew! Things are certainly heating up in the Valley.

It’s just one month into spring and we’re getting summer-like weather. Of course, we shouldn’t be surprised since we had spring-like weather this past winter.

While folks might not welcome the early season 90-degree temperatures, our crops are basking in the sun, As a result, some commodities, like almonds, are developing faster-than-normal due to the temperate weather, almond expert David Doll tells us.
Almonds are developing faster than usual in the Valley.
The well-known pomologist with the University of California Cooperative Extension in Merced County estimates the almond season is about a month ahead, which should translate into an early harvest – barring a sudden change in Mother Nature.

Last year you may recall that growers were harvesting their almonds a couple weeks early thanks to the drought. Well, another dry winter is fueling growth in other crops.

At the same time, the half-inch of rain we had on April 7 also helped give crops a little boost.
Indeed field scout Carlos Silva anticipates alfalfa growers to start their second harvest of the season later this week. In addition, he’s already seeing a number of fields with cotton seedlings already emerging from the ground. For the most part, cotton growers have finished planting around the Valley.
Growers are poised to do their second cutting of alfalfa.

Of course, we’ll have to see how a warm spring plays out on the pest front as well.

Carlos points out that weevils were on the rise in alfalfa. But the pests shouldn’t pose
 a threat with alfalfa ready for the second cutting soon.

In almonds, peach twig borer numbers have been relatively low in orchards. Navel orangeworm counts are up on the Valley’s west side and will merit a close eye. As we mentioned before, leaffooted plant bugs remain a concern for growers. Carlos has seen some nut drop in areas.
Cotton seedlings are starting to emerge.
Monitoring pests in the cotton fields will start ramping up. Carlos plans to begin scouting some of the faster developing fields for pests in the coming week. Let’s hope for a rather uneventful pest year in cotton this season.

Monday, April 13, 2015

Cotton, Baseball Seasons Move Ahead in Lock Step

Pro baseball is in the air and the local Fresno Grizzlies minor league team opened its season on Thursday. 

Yes, springtime also spawns optimism among fans and players that they will have a successful year.

Cotton and baseball are off to a marathon start to the season.
You might say the same is true for cotton growers, who also start their season in April. And like baseball, their season resembles a marathon rather than a sprint. Both starting in the spring and end in the fall.
In baseball, there’s the first pitch. In cotton, there’s the first seeds in the ground.

Field scout Carlos Silva reports some early bird growers are benefitting by the early spring warm weather. They should start seeing seedlings popping out of the ground soon. Typically it takes 180 to 200 days for cotton to go from seed to full maturity.

Just like baseball fans, growers look at the spring as a fresh start, feeling optimistic they’ll have a winning crop six months from now – even in a drought.

Cotton planting is in full swing in the Central Valley.
Speaking of drought, Carlos says many long-time cotton growers are continuing to stick with the crop, despite the four straight dry years. Still, we wouldn’t be surprised if there is another decline in cotton acreage in 2015. Last year, the drought prompted California growers to reduce acreage by 23 percent to about 215,000 acres. 

While cotton season is just under way, alfalfa is moving along nicely with growers completing their first cutting of the year. We’re hoping the water supplies will hold up enough for growers to continue harvests into the fall.

 On the pest front, weevils have been under control so far, according to Carlos. Blue alfalfa aphids have been on the rise, but the number remain below the threshold to treat the fields.

Monday, April 6, 2015

Keeping an Eye on Water Quality during the Drought

It’s no surprise we’ve been experiencing extremely dry weather.

But last week’s photos and videos of Governor Jerry Brown joining state water surveyors on Echo Summit near Lake Tahoe illustrated how dry it is.

Governor Brown (center) attends monthly snow survey.
It was no April Fool’s Day joke when surveyors stuck their poles into the ground and found nothing but dirt and grass. There was no snow to be found in an area that normally averages more than 66 inches of snow annual. 

Statewide, the snowpack’s water content is 5 percent of average, breaking the record 25 percent in 1977 and 1991. Ouch. We can expect no water from the meager snowpack as it melts in the coming weeks, according to State Water Chief Mark Cowin.

With that, Brown ordered historic water restrictions and called for water suppliers to keep track of water usage in agriculture. 

Water management certainly will become a major issue here in farm country. So will be pest management.

The fourth-straight dry year could see farmers dealing with a lot of pest pressures. That could lead to more pest treatments. That concerns Orvil McKinnis, a program manager with Summers Engineering, a Hanford water and irrigation management consulting firm.

The drought could create water quality issues this season.
McKinnis says increased chemical usage could impact water quality, which could raise a red flag to regulators. “The drought has lessened the amount of water that is in waterways, creeks and streams.” As a result, he says any chemicals found in the waterways will likely come in a more concentrated form.

At a recent field day, McKinnis told growers there has been an uptick in chlorpyrifos found in the waterways, reversing a downward trend. 

“I wanted to make a point with growers if we can’t get chlorpyrifos under control we’re going to lose the chemical,” he says.

Growers should weigh pest control options before treatment.
There are many options, including reduced-risk chemicals and biological controls.

“They should reach out for more information,” McKinnis says. “If they are not sure what to do they should ask. There is enough information available online, through their pest control advisors and other professionals that could answer any question.”