Q. In  mid-October, I planted 16 1-gallon lavender lantana across the ridge of a small hill in our backyard, spaced about 4 to 5 feet apart. The plants did not have well-developed root systems, as I think they had recently been transplanted from 4-inch pots.

The plants seemed to be thriving and because I was giving them extra water daily for a few weeks, I kept a good eye on them. About two or three weeks after planting, one of the plants disappeared. A small stub was left and the soil around the plant seemed undisturbed.

My fear was that I was going to lose all 16 plants, one by one. I kept an eye on the plants until the rains began in December and the other plants remained undisturbed.

Recently, I went up to the top of the hill and found that a second plant, the one right next to the first one taken, was gone also. Again, the ground was not disturbed and it seemed the plant was eaten to the ground, leaving only the roots.

What animal can completely remove a small plant so cleanly? A Google search indicates that lantana is not a plant that wild animals like to eat. We have squirrels running through our yard, but I don’t think they eat the plants. There is no evidence of gophers or moles. Why take one plant and then wait a few weeks to come back for another? Such a mystery!

Do you have any ideas on this?

Lynn Bak, Walnut Creek

A. Lantana contains toxins that attack the liver, making it poisonous to grazing animals, as well as pets and humans. However, not all animals have read the warning signs, and the two likely suspects in your mystery are deer and rabbits. My money is on the deer.

Lantana is considered a deer-resistant plant because deer don’t care for the rough, jagged leaves or the aroma from the blooms. Rabbits tend to steer clear of aromatic plants, too.

As these were new plants, however, the foliage would be tender and smooth, and there would be no aromatic blossoms. It’s likely a wandering deer ate the first plant down to the ground and then went on foraging. Weeks later, it returned — or another deer stopped by — and ate the second one.

As the plants get larger and bloom in the spring, they won’t be as appealing to the deer, although you do need to keep an eye out for caterpillars. As you’ve only lost two plants since October, you’re probably at a point now where the deer will leave them alone, or at least not eat the entire plant. You could try putting cages over them to keep the deer away, but that’s probably more work than it’s worth at this point.

Q. I have a mature lemon, a mature orange and a 3-year-old lime tree. This past year, when the flowers changed to fruit, I noticed a majority of the new fruit ended up falling off all three trees.

I have always seen some, but nothing like this. As a result, my orange tree has a mere 10 percent of what it normally produces. My lime had hundreds of new fruit, but only provided me three limes this year.

What’s up and is there anything I can do to reduce the fruit loss?

Dave Clausen, Pleasanton

A. There are a few reasons for early fruit drop in citrus. Small numbers of fruit drop is normal, especially when a tree is overloaded. In young trees, it’s common to lose a lot more, because the tree is not yet mature enough to support a big crop. However, it seems like you’ve had something far beyond this.

Excessive pruning can stress the tree, which senses that it’s in trouble and drops its fruit in favor of survival. A lack of adequate or consistent water can produce the same results, as can a severe pest infestation.

Because you’re an experienced citrus grower, you didn’t mention an insect issue, and as it happened to all three trees, I think we’ll have to blame Mother Nature for this one. Sudden changes in temperature can cause fruit drop, especially if we have a few days of very high temperatures as the fruit is starting to set, or shortly thereafter.

You can change your practices regarding pruning, watering and pest management, but we’ve yet to devise a method of controlling the weather. All we can do is weep over our meager harvest and hope for a better season this year.

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