Monday, April 16, 2018

Something is Already Starting to Bug Almonds This Season

Things are getting a little buggy for almond growers.

That’s not good news, especially this early in the season, reports almond field scout Jenna Mayfield. This concern compounds the trouble already experienced by growers because of the February freeze and March and April rains. Oh yes, we forget to mention the dry December and January weather.

The sun made an appearance in the Valley last week.
“It has been weird. There will be all kinds of crop losses,” Jenna says. But that won’t be known until harvest time.

After a number of growers wrapped up another application of fungicides a week ago Sunday, Jenna had time later in the week to venture into the orchards to inspect the progress of almonds. The nuts are a good size, she says. 

Young almonds are growing nicely.
But she adds:  “Leaffooted plant bugs are out there. Everyone is worried about that.” Jenna says growers are staying vigilant and keeping a close eye for signs of pest damage.

The leaffooted plant bug (LFPB) gets its name because of the leaf-like enlargements found on the hind legs. Adults are about an inch long with a yellow or white zigzag line across its flat back. UC Integrated Pest Management called LFPB a sporadic pest for almonds.

Damage can be significant when weather conditions are right. Here’s what UC IPM says: “Feeding by adult leaffooted bugs on young nuts before the shell hardens causes the embryo to wither or abort or may cause the nut to gum internally, resulting in a bump or gumming on the shell. It can also cause nut drop. After the shell hardens, adult leaffooted bug feeding can still cause black spots on the kernel or wrinkled, misshapen nutmeats.”

Experts say the bugs often show up in April in search of food after overwintering in nearby fields. Jenna noted she usually spots the pest in May. “They seem to be a little early this year.”

Here's a leaffooted plant bug.
Two indicators of LFPB problems are gumming found on the outside of the nut or aborted nuts on the ground. However, there is a seven- to 10- day lag between feeding and when the gumming and nut drop take place. By the time these signs are evident, the pest may have already moved on.

“Treatment thresholds have not been developed for this pest in almonds, but low numbers of bugs can cause substantial damage. If bugs and their damage are evident, consider an insecticide application; apply insecticides through May to target the overwintering adults that have migrated into the orchard," UC IPM says.

You can see the LFPB damage to the almond kernel.
“Unfortunately, the broad-spectrum products that are most effective against leaffooted bugs are also very disruptive to biological control agents of spider mites and other almond pests. Later applications are not needed when numbers of overwintering adults have declined or nymphs are the only life stage present, as their mouthparts are too small to feed on the kernel.”  It’s important for growers to weigh the consequences when they are making an insecticide choice to avoid secondary problems that can flare up after use of broad spectrum materials.

Given the all the weather issues and early pest concerns, growers are pressing on and “hoping for the best,” Jenna says.

Monday, April 9, 2018

Warm April Showers Prompts Growers to Protect Almond Trees from Disease

The Pineapple Express rolled into the Central Valley at the end of last week, delivering warm rain to our region.
Variable weather hit almonds, including a hard freeze.

Like we mentioned last month, this wet stuff during the late winter and early spring continues tobewitch almond growers who are still trying to assess any damage from the freezing weather in February. 

David Doll, a UC Cooperative Extension pomologist and almond expert in Merced County, says the April showers may prompt almond growers to make another fungicide application.

“If a spray has not been made within the last seven to 10 days, consider making a spray with a rotating chemistry to reduce the occurrence of the spring time diseases of Anthracnose, scab and shot-hole. If there is a history of bacterial spot, a copper-manzate application should be considered,” Doll wrote in a recent Almond Doctor online column.

So far this season, Doll has observed cases of leaf lesions caused by bacteria. This condition, which is evident by a yellow halo on the leaf, could be compounded by more rain. Trees eventually recover after losing some leaves.

Almond growers need to protect trees from scale.
On the pest front, Doll recommends growers putting out traps and monitoring for navel orangeworm (NOW).  Orchards with a lot of mummy nuts are likely to need treating for NOW in the spring. Those growers who did a good job with orchard sanitation “are not going to have much value in a spring spray,” Doll told growers attending a recent almond field day.

Meanwhile in the fields, field scout Damien Jelen says the rain has slowed some cotton planting. A lot depends on the soil. Some soil will dry faster and allow growers to get back into the field and finish planting.

Alfalfa growers are finishing the first cutting of the season.

In alfalfa, growers have completed[ their first cutting. Now, Damien says, they are waiting for the cut alfalfa to dry more on the ground before baling the crop.

Monday, April 2, 2018

Cotton Planting a Matter of Degrees for Valley Growers

We’ve turned the page on another month. Welcome April.

To cotton growers, that means getting their crop planted. Field scout Damien Jelen reports growers were busy working their fields in the past week, redoing beds pounded by the recent rain storms.
Cotton fields are ready for planting across the Central Valley.
“Cotton season is ready to roll,” Damien says. Some growers even worked over the weekend to prepare for another year. Planting, he adds, “depends on the soil temperatures.” Plus, growers will need for the ground to dry enough to get their equipment out in the field.

It’s a matter of degree days to decide the right time to plant.

Since early March, growers have been keeping track of the temperature readings in their fields. UC IPM provides daily temperature readings on its “Cotton Planting Forecast” online site.

Good stand establishment requires sufficiently warm air (measured in heat units) and suitable field soil temperatures,” UC IPM says. “Cotton seed requires approximately 50 degree-days to accumulate in order to emerge when planted at an optimum planting depth. It is also important that temperatures be consistently warm and don't drop during the first five days after planting.”

In the Valley, the first day growers officially can plant their cotton is March 10, which represents the end of the 90-day host-free period for the pink bollworm control program. Of course, there usually aren’t any early birds that start on the 10th


UC IPM offers these guidelines for interpreting its five-day forecast for determining field soil temperature readings:

  • 10 degree-days or less are unfavorable for planting.
  • 11 to 15 degree-days are marginally acceptable for planting.
  • 16 to 20 degree-days are adequate for planting.
  • Greater than 20 degree-days are ideal for planting.
  • Be cautious about planting if cooling temperatures are forecast over the course of the 5-day period.
“Couple the five-day forecast with soil temperature readings from a number of locations in your field. A soil temperature reading of 58 degrees to 60 degrees taken at 8 a.m. is considered the minimum temperature required for good stand establishment, as long as the five-day forecast predicts favorable conditions for the next four days,” UC IPM says

Take soil temperatures in six separate field locations.
Farm advisors say measurements should be taken in six different locations to get the average field temperatures. A soil thermometer probe should go down to planting depth to take a reading.

After the crop is planted, cotton seedlings should emerge from the ground within 10 days. That indicates good germination.

Damien expects planting conditions to be ripe this week, meaning a flurry of activity in the cotton fields.

Meanwhile, Damien also anticipates alfalfa growers to do the first cutting of the season this week. The dry weather and 80-degree temperatures in recent days – after heavy rains to start the spring – has dried the crop enough for the first harvest to take place. As long as there’s plenty of water and nature cooperates, look for the alfalfa season to stretch into the early fall.

Monday, March 26, 2018

Alfalfa Growers Wait in the Dugout as Rain Delays First at Bat to Harvest Their Crop

Like baseball, spring signals renewal and optimism – a fresh start to a new season.

 But the first week of spring hasn’t been very spring-like. The rainy weather you might say has left farmers in the dugout waiting to start the first harvest of the season.

Certainly,growers have been looking forward to a strong year after seeing a rebound in 2017 when water supplies opened up after the end of the five-year drought. 
Alfalfa fields are about ready for the first cutting of the season.

The early March rain followed by several days of mid-to-high 70-degree days turned alfalfa fields into a sea of green, resembling the lush outfield grass at the ballpark. “Harvest is just around the corner,” says field scout Damien Jelen.

 But last week’s downpours, which dumped more than 2 inches of rain over three days in many Valley locales, have produced a rain delay. 

“It could be days before growers can get out into the fields,” he says. “The first cutting is very critical.”

Damien says the early dry winter could signal big pest problems for growers this season. “The worms could hit hard.”

The early season alfalfa harvests produce the best quality crop. As a low-value crop, it’s important for growers to take steps to protect their investment.

Make adjustments to the harvester during the first cutting.
Here are some tips for harvesting alfalfa after the rain:

  •   Make sure the mower/conditioner is properly adjusted. The first-cut alfalfa is usually heavier and thicker than the later season crop. As a result, cutting requires more pressure from mowers. However, too much roller pressure could create excess leaf loss. For roller conditioners, check the roller clearance and pressure to ensure they are where they need to be. Proper speed and clearance are important for impeller conditioners.
  • Wet alfalfa can be spread out to dry in the sun.
  • Make the windrow wider. If drying is a challenge, lay the alfalfa in a wide swatch to increase exposure to the wind and sun.
  • Cutting higher will help air move around the windrow, allowing for quicker drying.
  • Time your cutting. In drier areas, cutting later in the day is better. In more humid regions, cutting in the morning after the dew is off is better.
  •   Rake only if necessary. Growers may have to rake if the cut alfalfa gets rained on. If that’s the case, raking should be done when the moisture content is 30 to 40 percent. This will balance leaf loss with good drying.  Consider using a chemical aid to prevent moisture damage.

 Let’s hope nature cooperates and lets alfalfa growers start working their fields soon.