California Almonds: Plenty Of Rain, Plenting Of Rethinking? – AgFax Tree Crops

OVERVIEW

Rainfall amounts? This week’s issue sounds a good deal like a weather report. Considering how much it’s rained and how much rain remains in the forecast, that’s not surprising.

Decisions about fungicides are likely on the table across all crops.

Insect and mite activity will throttle back at least in the near term. Along with the rain, temperatures are running significantly below normal.

CROP REPORTS

Franz Niederholzer, UC Farm Advisor, Sutter/Yuba Counties:

“It’s been wet. Starting yesterday (5/15), it rained almost an inch on the west side and 2 inches in places on the east side. That’s a lot of rain for any storm here, but particularly in mid-May.

“It’s kind of showery today and more rain is in the forecast for the weekend, with chances next Monday through Wednesday. There are puddles right now but nothing outrageous.

“Heat units have been running short. The high today, depending on the location, was supposed to be 58 to 63. That’s probably more of a factor for guys with annual crops like tomatoes and rice. Right now, it’s 20 degrees under normal.

“If the weather people are right, the high will flirt with 70 tomorrow but maybe not get there until the middle of next week. By contrast, the record temperature for today (5/16) is in the low 100s.

“With rain or the threat of it, a lot of spray rigs were moving around the countryside this week. Growers have been spraying orchards – particularly walnuts on the east side – and with good reason. Not much bug activity, and we don’t have the conditions to push them along.

“In almonds, we’re in kernel fill in most varieties. Growers are thinning prunes.”

Jhalendra Rijal, Area IPM Advisor, Northern San Joaquin Valley:

“In areas around Modesto, we had rain yesterday (5/15), then last night and also this afternoon. A lot has fallen, considering this is California in mid-May. Amounts varied, up to an inch in places.

“More is in the forecast over the weekend and into next week. Temperatures over the next 10 days will be cooler – not going above 80, with a couple of days below 70. With those conditions, insects and mites will slow down.

“So far, insect activity has been moderate, nothing outrageous. With earlier rainy weather, everything started a little late this year, anyway. In certain cases, pest trends are running 2 weeks later than normal.

“The NOW are probably ending their first peak flight this week. One indicator of delayed development has been the timing of the May sprays, which typically happen in the latter part of April. This year, applications were mostly timed in the first week of May.

“I’m hardly hearing anything about mites, and with the current weather I don’t expect them to make much of an appearance for a while.

“In walnuts, codling moths started picking up. They were generally in the normal time range, maybe a bit on the later side of it. Based on trap counts in orchards we monitor, the 1B timing should be in the third week of May, around May 25. That timing can vary, of course, depending on the orchard. 

“I was on one farm call this week where the grower had a relatively high level of damage in almonds by plant bugs or stink bugs. We weren’t able to find any insects that might have caused it. We are finding brown marmorated stink bugs in almonds and peaches. The first sightings were in April and that is continuing. Stink bugs have been active on the east side of Stanislaus County in almonds.”

Dale Deshane, PCA, Supervised Control, Bakersfield:

“Rain has been chasing me all day (5/16). Every time I get somewhere, it starts raining again. So far, the big rain came last Friday (5/10). In one location near Edison – which is east of Bakersfield – the total hit 2.25 inches. In other places south of Bakersfield, the amounts ran from 1.5 to 1.75 inches. Around Mettler down by the Grapevine it rained 1.5 to 1.85 inches. Again, that was a week ago. For this time of the year, that is a lot of rain, although areas north of Bakersfield didn’t get too much during that period.

“Showers today have been light and it’s been raining off and on, but rain is in the forecast for the next 4 to 5 days.

“Before the rain, mites had started moving into the middle of almond trees, and we sprayed quite a few blocks the week before the rain. We’ll see how things look next week. Also, we knocked down green stink bugs last week.

“Rust is starting to pick up a little more. Alternaria is, too, especially in the Montereys. These are ideal conditions for it – rain every few days. I’m afraid it will really take off once the weather warms up again and humidity sets in.

“We were putting out ant bait but then temporarily pulled back on that due to the rain. Herbicides have been going out here and there.

“In pistachios, we started our nutrient spray and the first spray for the little bugs. Most of our pistachios are in the Buttonwillow, Shafter and Wasco areas, and they missed the rain, so we didn’t include a fungicide. With this current round of rain, we’ll see what happens.

“The first alternaria spray in pistachios is going out where we had big blowups last year. But with all this rain, we’ll probably go across everything at least one time. That probably will happen in the tail end of June unless it rains a lot more before then.

“In cotton, we’re pretty much going across everything with a miticide and Roundup ahead of the first water. We saw a few spikes with worms and some people sprayed. But in my cotton, they seemed to cycle through. Mainly, we’ve found cabbage loopers and small numbers of beet armyworms.

“We’ve started sweeping some of our biggest cotton and are picking up lygus counts at 1 to 4, and that cotton isn’t even squaring yet. Some is pushing the sixth leaf and should be squaring next week.

“Alfalfa is pretty quiet. We started finding a few beet and yellow-striped armyworms, but nothing is taking off with this cooler weather. My truck’s thermometer (late afternoon, 5/16) reads 64 and that’s the warmest it’s been today. Mostly, it’s lingered in the upper 50s.

“In tomatoes, we’re applying sulfur for mildew and treating for late blight. Late blight hasn’t appeared yet, but with this rain that could happen. Late blight scares me because it can hit fast and destroy the whole plant. That’s a big concern with this weather. We’ve made 2 to 3 applications in tomatoes for bacterial speck. Again, we haven’t found it yet, but this rain could bring it out.

“Looper treatments went out in tomatoes in a few places. They had built enough that you could see defoliation starting in vines as you walked down the rows. This is kind of unusual because I haven’t treated for loopers in tomatoes for 7 or 8 years. These were cabbage loopers.

“No armyworms in tomatoes yet, but they probably will show up as soon as it gets hot. We’re also treating a few carrot fields for a variety of worms. Rust started popping up in the garlic and we’re making our third spray in some fields. Traces of downy mildew turned up in onions and we’ve seen several strikes of late blight in potatoes since that last rain.”

Aaron Heinrich, Independent Crop Advisor, AgriWest, Inc., Escalon:

“At my house in Ripon, it’s rained just over a half-inch. A client in Escalon – a few miles north of me – had three-quarters of an inch in his gauge. But as intense and concentrated as these thunderstorms were, it easily could have rained over an inch on one road and less than a quarter-inch on the next road over.

“Regardless, this has been a significant rain and field work has stopped. Rain is still in the forecast to some degree for the next 5 days (from 5/16) and on Saturday the chance for rain is 100%.

“In almonds, we haven’t seen a lot of mites yet and this weather may slow them down a little by washing them off the leaves. We’re fine tuning our nitrogen rates for those final applications we’ll make before June 1. A little weed spraying had been under way and some people took advantage of the rain forecast and applied preemerge herbicides.

“Codling moth sprays for the 1B flight in walnuts are timed for next week. Maybe 10% of our walnuts will be sprayed for codling moths. Those will be in blocks with earlier varieties and where mating disruption isn’t being used. We’ve had to spray a few blocks for fruittree leafrollers, but that’s winding down. We’re now starting to monitor for aphids in walnuts.”

AgFax Tree Crops is published by:

AgFax Media LLC,  142 Westlake Drive,  Brandon, MS 39047-9020.   

601-992-9488,  Owen Taylor , Editor and Publisher.

For subscription inquiries, please contact Laurie Courtney

© 2019, AgFax Media LLC