Dying grass is often not a disease, but caused by poor irrigation

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It is starting to get hot. If your lawn is showing that "disease" where it turns kind of smoky grey and then dies, you have that horrible irrigation disease.

In truth, many of our lawn diseases on tall fescue do not pop up for another month or so.

The problem is either that the sprinklers are not giving good coverage or the soil beneath your lawn is compacted and the water is flowing to low spots before it penetrates. It is not a disease.

If you see a lot of puddling after an irrigation, it needs to be aerated. If the "disease" is either right next to an irrigation head or nearly exactly halfway between them, then it is probably poor irrigation coverage.

If you have a lawn, you should be aerating once a year and checking the irrigation just before it gets hot. Both lead to lots of wasted water.

Irrigation systems with too much pressure for the irrigation heads will fog, or mist when they are spraying and not create the drop.

This will lead to a lot of water waste. Have someone install a pressure reducer on the outside water line. It should have been installed anyway.

For lawn lovers who are tired of their fescue lawns, I may have a deal for some of you.

If you are familiar with buffalo grass, I am testing a new variety for this area, partnering with a producer from Nebraska who has started a sod farm in Pahrump.

He has agreed to supply buffalo grass to some local homeowners who are sick and tired of their fescue.

Buffalo grass water use is one of the lowest. It needs infrequent fertilizer applications; takes heavy traffic as well as light shade; but does turn brown for about three to four months in the winter.

To learn more about buffalo grass, visit www.toddvalleyfarms.com/buffalograssfaq.

Question: I have a bunny-ear cactus with about four years of growth, lots of love and fertilizer and it is doing great.

This year, several of the lobes have lots of babies budding up, some as many as 17 or 18.

Do you cull any of them out, or let them grow some and then thin? I can't imagine all growing off of one parent.

Answer: The plant will handle the problem all by itself if you let it and don't mind them being a bit crowded.

The pads, as they grow, will force other pads off and self-thin, or you can do it yourself by using a sharp, sterile knife, cutting right at the joint between the baby pad and the mother pad.

You can plant these if you like. You can take off any of the pads from your cactus, allow them to heal over for a week or two in the shade and then plant them one-third below ground and water them once a week to get them to root.

You could cut the remainder off or just let them develop into branches with more pads. It is quite interesting that way.

Q: My Mediterranean fan palms are starting to flower and eventually they create a mess. Can I now prune the small clusters without doing any damage?

A: You can cut off the flower and seed shoots any time without harming the palm tree. Removing unwanted flowers or fruit will help funnel that energy into growth instead of fruit production.

Q: How often should we replace the bark mulch in our tree and plant wells, or can it be left forever?

And how can we keep our landscapers from blowing the mulch away when they are trying to blow away the fallen leaves?

A: The mulch is left in place and left to rot into the soil if water is present. This will help to transform your highly mineral soil, with very little organic matter, to one that is more organic.

This improves the general quality of the soil for all plants tremendously. You can rake the mulch to renew the color again. Just disturbing it makes it look refreshed.

You can spray it with a hose to wash the dust and dirt off, as well.

I would tell the landscaper to use a rake instead of a blower, or you can use coarser mulch that won't blow as easily.

But they will not take the suggestion of using a rake seriously. Everything they use now has some sort of small engine attached.

I would rake it myself. By the way, our mulch, available at the Orchard, didn't blow at 70 mph winds. It is because it interlocks due to the varied sizes of the chipped wood.

Q: We had "thrips" curling our mature ash tree leaves last summer, so we sprayed it heavily this January with Dormant Spray.

Should we spray it again now that it is leaving out, and if so, which spray do you recommend?

A: The curling leaves on ash are probably the ash whitefly -- very difficult to control.

In the past, this insect could not tolerate the summers here and is very short-lived. I hope this is not changing. Usually, we would get damage the first couple of years after planting and it would disappear.

Dormant sprays and oils will not control it. I would try to tolerate it as best as you can, and if it isn't causing a lot of damage, I would try to ignore it.

If you can't, then it would be best to call in an arborist to get the proper insecticide sprayed onto the tree to get some control. Chemicals that they might try would be called Merit or Marathon. You might not be able to get these.

Q: I have a Mulberry tree that is putting on berries. They are a creamy white and are already ripe.

I thought they were supposed to be a dark purple when they get ripe. What gives? Is this an albino? Are they safe to eat?

A: There are two forms of mulberry used for fruit -- one purple and one white. Morus alba is the white fruited form and is from China. The purple form, Morus Nigra, comes from the Mediterranean region.

Both types are safe to eat and both make a good wine, can be eaten in salads, etc.

They probably selected the white form since it does not stain as badly when it falls or is dropped by birds.

The white fruited form has been traditionally used for feeding silkworms, although both will work.

Q: Major grief with my 12-year-old pistachio. Last year, and now this year, the clusters of young nuts turn brown and die.

Before that time, I was able to get terrific harvests of pistachios. I found several of the leaf-footed insects that were on my pomegranate last year but actually did no harm. Please advise.

A: You most likely have the leaf-footed plant bug running havoc in your pistachio tree.

Take a look at this Web site from the University of California: www.ipm.ucdavis.edu/PMG/r605300311.

You can try Neem and Spinosad, but I think you will have to apply permethrin as this site recommends.

I tried to find a label for you locally that contained permethrin, but couldn't by calling around. Most garden help will not know.

You will have to go to one of the nurseries and look at the ingredients on the label.

Look for permethrin in the ingredients and make sure the spray is labeled for fruit and nut trees. Follow the label directions. They will tell you how much to mix for spraying.

There are knowledgeable employees at some of the companies in town. I am just not at liberty to direct you.

Wear protective clothing, covering your head, face, neck, hands, arms and spray when it is windless or very calm.

Immediately shower afterward and wash these clothes separately from others.

I am not trying to scare you, but I want you to be safe around these harder pesticides like permethrin, which actually has a fairly low toxicity for humans.

Bob Morris is a horticulture specialist with the University of Nevada Cooperative Extension.