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Grasshoppers can be destructive to yards

Grasshoppers in Southern Nevada hit the national news. They’re not a problem for humans or large animals because they carry no diseases and they don’t bite, but let’s talk about your home yard.

Just like anything else that’s living, grasshoppers need something to eat and something to drink. Home landscapes provide both water and food. So do resort landscapes. So why leave? Looks like they will be here until fall, when cooler temperatures arrive.

Our very wet spring made all this happen. Our spring rains also caused diseases like bunch rot on grapes to occur when it has been rare here in the past. It caused leaf diseases that defoliated some varieties of peach trees. Cicadas came out of the ground in abundance, and their mating noises attracted the wasp-looking cicada killers as well. In short, our weird spring caused many weird things to happen in our desert.

Grasshoppers or locusts? Locusts are social grasshoppers. Whereas grasshoppers operate alone, locusts operate en masse. Locusts make legends with their voracious community swarming and appetites. Locusts feed and destroy everything in their path. Grasshoppers don’t. Their voracious appetites aren’t legendary, and their huge mandibles don’t bite people but can take some big chunks out of garden and landscape plants. Grasshoppers are destructive but not like locusts.

Grasshoppers start cute and small with small appetites and jump from plant to plant. But as they grow bigger, their increased appetites cause more and more damage. And they can fly, rather than just jump, when they get older.

The time to control them is when they’re small, not wait until they get big. That means to control them early in the year. Don’t wait until they are a bigger problem later.

When they’re small is also the time to use a biological control they can eat such as Nosema-impregnated bran flakes. That is a very effective bait when used early in the year but not nearly as effective when used later.

It can be bought online. They can have several different names, but look for the words “Grasshopper Bait” or “Nosema locustae.” I don’t think you will find it available locally.

Buy it right after spring rains occur and apply it when it’s no longer raining. Get your neighbors involved and apply it at the same time to get better widespread control.

Of course, chemical sprays such as Sevin insecticide kills grasshoppers, but ducks and guinea fowl will chase them down and eat them — an alternative to chemical sprays. Notice I didn’t mention chickens. Chickens and raised bed gardens, in my experience, are incompatible.

If you can’t have animals roaming around in your yard, try hot pepper sprays to repel these critters. I have never used it, but there are anecdotal stories that says it works.

Q: This year I had swarms of huge wasps flying around my yard. I followed them and found they dig pretty big holes in the ground. How do I get rid of them? They look pretty scary.

A: Maybe you don’t want to. These swarms of large wasps that you see are probably cicada killers. They are chasing down the cicadas you hear buzzing in landscape plants. Cicadas are out in record numbers partly because of our heavy spring rainfall.

Wasps dig a hole in wet soil, track down a cicada by following the noise they make and take it back to their pre-dug hole in the ground. They sting the cicada, paralyzing it, and lay eggs for the next generation of cicada killers. This paralyzed cicada is a buried food source for their babies to feed on until they emerge next year.

Cicada killers are good guys for us, at least, and rarely sting a human unless they are provoked. But they can be intimidating, and if they do sting, it is extremely painful.

There are traps you can buy online and hang in your landscape plants that will reduce their numbers rather than using insecticides. These traps won’t hurt or attract honeybees.

If you need to use a chemical pesticide, spray it down the holes they created in the soil rather than spraying the entire area.

Q: I have one peach tree dropping its leaves. The leaves are yellowing, dropping, and the branches at the top of the tree are bare. Also, it has small fruit that never got very big. The other peach tree I have is fine and produced large fruit and no leaf drop at all. What’s going on?

A: Blame it on the spring weather. Some varieties of peach will drop their leaves after a change in weather. These branches aren’t usually dead, and new leaves will develop a week or so after leaf drop. These new leaves come from leaf buds that developed in late spring and early summer.

While you’re waiting for new leaves to grow, check these naked branches at the top by bending them to see if they are supple. If they are supple, then this is a sign they are alive and will probably grow new leaves. This “nakedness” is only temporary.

While you’re at it, check for borer damage on any of the limbs or trunk that supported these naked branches. Borer damage will face the direct sunlight on the upper surfaces of limbs or on the trunk facing south or west. You probably won’t find any, but if you do, remove any loose bark down to fresh wood. A sharp, sanitized knife can help you do this.

The development of new leaves presents you with an opportunity. If the leaves that dropped showed any signs of yellowing earlier, now is a great time to apply iron fertilizer to the soil to help new leaves coming out to be dark green instead of yellow.

Iron fertilizers applied to the soil work best before new leaves develop on branches. If you applied a general fertilizer for the tree earlier in the season, there is no need to apply more.

Some trees are naturally smaller than others. To get larger fruit, you will have to remove more fruit during thinning so that the remaining fruit gets larger.

Q: About two years ago I planted a “fruit salad” tree that had three varieties of peaches. I was stunned to find them ripening at the beginning of July and thought I could harvest them and enjoy them. Most of them looked fine. but quite a few are rotten and brown. Any suggestions you have would be deeply appreciated.

A: The picture of the tree you sent shows a tree that’s not very healthy. It’s still small and scraggly after two years in the ground.

Peach trees I planted this spring, for example, are now nearly 5 feet tall, dark green and so dense that you can’t see through them. And that’s after I pruned them just after planting.

The fruit that’s no good was damaged by intense sunlight. That can be prevented if the tree puts on a lot of growth in the spring and the dense canopy protects the fruit from sun damage.

The poor growth of this tree is either from a poor planting technique, a watering problem, a fertilizer problem or a borer infestation in the tree, probably in the trunk because of its age. It’s hard to detect new borer damage in young trees.

To check for trunk damage by borers, bend the tree over to about a 45-degree angle. If the tree trunk doesn’t make a noise like it’s cracking or snapping, there aren’t any borers in the trunk. If it does make those noises, the tree is infested beyond repair and should be replaced this fall or next spring.

Getting that tree off to a good start is mandatory. Plant it the same depth it was in the nursery container. Dig the hole for that tree the same depth as the container but about five times wider. The soil coming from that hole should be mixed with good compost before it’s put back in the hole around its roots and watered in. Stake the tree so its roots don’t move during the first year of growth.

The first year after planting, 90 percent of your efforts should be focused on developing good branch structure and increasing the size of that tree. The second year in the ground, 50 percent of your efforts should focus on developing good tree structure and 50 percent focused on future fruit production. The third year, 90 percent is focused on future fruit production and 10 percent on its structure.

Never water the tree daily. Apply enough water under the canopy of the tree so that it doesn’t need another irrigation for at least two days during the summer. If a high-quality compost was added to the soil at planting time, no fertilizer is needed for at least the first growing season. Maybe longer.

Bob Morris is a horticulture expert and professor emeritus of the University of Nevada, Las Vegas. Visit his blog at xtremehorticulture.blogspot.com. Send questions to Extremehort@aol.com.

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