#6 Pesky Pests Spring, Jackie Lee- Arkansas Blackberry School
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#6 Pesky Pests Spring, Jackie Lee- Arkansas Blackberry School


[Music].>>Hello. My name is Jackie Lee and I’m the horticulture
IPM specialist for the University of Arkansas Cooperative Extension Service. And today I wanted to talk to you about some
pesky spring pests that you’ll encounter in blackberries
First off, I think it’s important to just recognize that we have a lot of identification
help for both insect pests and disease pests. And it’s great to remind your stakeholders
that they can contact their local Extension agents. They can place plants in paper sacks, not
plastic, to be sent for diagnosis. And to send the whole plant if that plant
is wilted. Because it’s very important that the diagnostician
receives the roots. Also, high quality pictures can be sent in
and emailed to your local Extension agent. Or your Extension specialist. So the first time period I would like to speak
about is when the shoots are 6 inches long to prebloom. So during this time period, we’re going to
see a few different types of pests, both insects and diseases. And the first insect pest we’ll start seeing
is the strawberry clipper. And then some diseases is cane and leaf rust,
orange rust, and yellow rust. So a little bit about strawberry clipper damage. The strawberry clipper lays eggs in the developing
buds. Those buds will be clipped and fall to the
ground. The larvae will feed within their flowers,
crawl out of the flower and pupate in the soil. The adult beetle will emerge and then it will
overwinter in debris. This is what that adult beetle looks like
It’s actually a weevil, which means it has a really long snout. It’s fairly small. You can see it in reference to the size of
that bud right there. And they start emerging in April and May. And this shows the damage. You can see the clipped buds. It looks like the little flower bud is just
about to fall off the plant. And then if you look in the top right, you
can see where the buds have already fallen off and been clipped. You can monitor for strawberry clipper. And this is what we recommend doing weekly
after first bloom. You want to check 100 clusters for clipped
buds or stems. If you find 1% clipped buds or any new newly
clipped buds, you want to recommend spraying You can also just monitor the clusters by
beating them over a white tray. You want to do about 100. And if you find any weevils, you want to recommend
putting out a pesticide spray. Now, these pesticides should be applied at
10-day intervals. Until there are no weevils present and no
new damage when you’re monitoring. For strawberry clipper control, there’s a
few insecticides labeled. And you want to refer to your bramble spray
guide or your local state spray guide. There’s a great spray guide that you can download
from the Southern Region Small Fruit Consortium Web site. And that has everything specific to brambles. And a few things that are labeled are Danitol,
Actara and Sevin. Now I want to talk about the rusts. And the rusts are a little bit complicated. Because they all look the same. But their management is quite different So
it’s very important that if you see rust, that you get it identified correctly. So send it into a diagnostician that has experience
with rust. And this will help you out. Applications for rust should start soon after
bud break. And continue about every 10 to 14 days. Remember it’s very important to rotate the
FRAC numbers. And look at the restrictions on your fungicide
labels. Rust can build resistance to fungicides. And that’s why this is so important. So right here, this is yellow rust. And yellow rust, you can find it on the undersides
of leaves. And we’re seeing this quite a bit more in
our blackberries than we have in the past. To manage yellow rust, you use fungicide applications. Refer to your spray guides and a couple of
examples of things you can use is cab Rio or pristine So it’s managed fairly easily
with just some early fungicide applications. Cane and leaf rust. The floricanes are usually the first to show
symptoms. This looks a little bit more orange. It can be found on the canes and the leaves. The management here, you want to make sure
that you prune out the infected canes. Because they are not productive. Also, you want to start a fungicide program
to help prevent the spread of this rust. The next one is orange rust. Orange rust is the most pathogenic. You can see that it causes these large orange
pustules on the bottoms of the leaves. It really weakens those shoots. You want to remove the whole plant in the
spring that’s infected. And then a start fungicide program to help
prevent the spread. So the next time period I want to talk about
is the bloom period. During the bloom period, the rusts are also
going to be an issue. But the management is really the same as the
6 inch shoot period. And then we have a host of other diseases
that become diseases, botrytis gray mold, anthracnose, cane blight, spur blight, and
powdery mildew. I’m going to talk about a few of these
So first off, botrytis. Botrytis has been a huge issue for us the
past two years. We’ve had really cool wet springs, which is
just ideal for botrytis to reproduce. Botrytis causes dried up berries and the fruit
to rot. And it produces this gray fruiting body. So sometimes you’ll hear this referred to
as gray mold. A great way to help lessen botrytis load out
there is to make sure your plants are pruned correctly. Because air circulation helps drying of the
plants. Which really, really helps with not just botrytis
control but with a lot of different diseases. You can use fungicides for management. A good fungicide management program in place
will definitely help with botrytis. Next off, anthracnose. Anthracnose causes purplish spots on the canes
in the leaves. It can also cause the drupelets to look dry
It looks similar to botrytis, beside you won’t see the gray fruiting bodies. Dormant applications are the most important
for combating anthracnose. This year we had a lot of growers that missed
the time period for dormant application. Everything was running ahead. We had sort of a warm early spring. Generally this application would go out in
early February. And it would be lime sulfur or Sulfurix. You want to continue with fungicide applications
after that first dormant application, if there is heavy pressure. If you see a lot of those lesions on those
canes, continue fungicide applications. Cane blight. I’ve seen this increase over the past few
years. It’s really bad in wet years. And what you’ll see is dieback of the canes
and the canes will look sort of grayish. If you get a hand lens and look at them closely,
it will look like pepper all over the outside of the cane. To manage for cane blight, you can use fungicides
at 6 to 8 inches, then 12 to 15 inches. And then you want to do another application
3 weeks later Also, you can utilize some cultural techniques. Pruning can be effective, if you use tipping
techniques instead of severely pruning. That helps a lot with managing cane blight. And then also you want to get rid of any infected
canes. Spur blight. Spur blight generally has not been an issue
for us. It may be in other areas. But you’ll see a darkened area around that
fruiting spur. And it will completely destroy that fruiting
spur. So something to be aware of and look out for. The next time period I wanted to talk about
is petal fall. During petal fall, we have a couple of insect
pests that are pretty important. We have our stink bugs and our red-necked
cane borers. Now, stink bugs, there’s two main types that
are problems for us. The brown stink bug on the left. And then the green stink bug on the right. Now, the adult stink bugs have wings that
come all the way down to the tips of their abdomen. The nymphs do not have fully formed wings. And you can see on the right with the green
stink bug, the nymph looks quite different than the adult. It’s sort of black and green and has some
orange spots. The adults will emerge from debris in around
April and then they will mate. They lay eggs in May. And the eggs are generally white barrel shaped
eggs that are laid in clusters May to harvest the nymphs and adults will feed on the fruit. And the fed on fruit actually tastes like
a stink bug. So not very appetizing at all. It also causes deformed drupes you can see
on the picture on the left. The picture in the middle just shows you that
there are different sizes of nymphs. So each time that nymph will molt and grows
a little bit bigger until it becomes an adult. And then that last picture shows the barrel
shaped eggs and the little stink bugs emerging. Stink bug monitoring is important. You can monitor clusters for the stink bug
nymphs. Also there are traps available. So you can use a yellow pyramid trap baited
with a pheromone. We make our traps out of plywood. And then we use a mesh screen to make a funnel. And then we just invert another mesh screen
over the top. It makes a really great trap. You want to make sure to time your insecticide
sprays to manage the nymphs. And you’ll be much more successful with stink
bug management. Because the adults are very difficult to manage
with insecticides. Here is some data that Dr. Donn Johnson and
myself put together a while back looking at different efficacy for different chemicals. And you’ll see Actara did a really great job
on stink bug. We also had some success with spin know said. And refer to your spray guide to see what’s
registered in your state. And then also you can look at the Southern
Region Small Fruit Consortium guide. And Actara, Brigade and Danitol are labeled. One thing to keep in mind with these insecticides
is there’s always a preharvest interval And some of these are at least three days. So keep that in mind. And then another thing Mustang max is registered
for spotted wing drosophila control. The PHI on this is one day. And if you’re managing for spotted wing drosophila,
you’re probably picking up some stink bug control. The red-necked cane borer. The red-necked cane borer is a buprestidae
beetle. It has sort of a metallic red neck. That’s where it gets its name You can see
that in the bottom picture. The adults emerge in late April to July. The beetles will feed on the primocane leaves
and then they will lay their eggs on the cane and the larvae will chew into the cane. And it causes tissue to form around the larvae
that creates this gall. And this gall can girdle that cane and reduce
the winter survival of your canes. You want to monitor weekly, starting in May
for the adults on the primocane leaves. And then in March, if more than 5% of those
canes are galled, you want to begin cultural control, which just means pruning out those
infested canes and burning them By April 1st, if you have more than 5% galled
canes, you want to put out a soil drench of Admire And that will do a good job. I just want to mention weed control briefly. You can utilize preemergent herbicides in
blackberry production. I recommend applying them at multiple times
during the year. The first application, it’s always good to
get out in November or December, to help combat winter annual weeds. And then to come back in in February so you
can get ahead of your spring weeds. There’s a couple of post emergent herbicides
you can use, Sandea and Poast. And then a lot of folks also use Gramoxone
for cleanup. But make sure that you refer to your state’s
spray guides to see what’s registered in your area. Also utilizing mulch, if it’s a smaller planting. And then landscape fabric can do a great job
for weed control. Here is an example of a study that we’re doing
with some preemergent herbicides. The picture on the left shows Surflan and
Sinbar. And this was applied in February. And then the picture on the right is our control. And you can see that we have done a really
great job with our grass in broadleaf control there. And just really quick wanted to point out
resistance management is very important. And in your spray guide, you can see that
on the right-hand side under the comments, it is listed the FRAQ or the IRAQ code. And just make sure that you always recommend
rotating between these numbers And not spraying more than twice before you rotate. [Music] ***
This is being provided in a rough-draft format. Communication Access Realtime Translation
(CART) is provided in order to facilitate communication accessibility and may not be
a totally verbatim record of the proceedings. ***

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