Spider Mites Attack Junipers
Neil Sperry
DEAR NEIL: What would cause big juniper trees to die? It appears to start on one side, but neighbors have lost entire trees.
It could be spider mites. Thump some of the declining twigs over white paper to see if you see nearly microscopic mites moving about. Kelthane is the best miticide. It could also be leftover damage from the several years of intense drought, and junipers will also brown and die when they shade one another. If those don't hit it you might want to hire an arborist for an on-site visit.
DEAR NEIL: Enclosed is a leaf from a Bradford pear near our house. At first the tree was dark green and flowered well but now the leaves are all yellow and there have been no blooms. What can we do to turn it around?
Bradford pears have short life expectancies - generally in the 8- to 10-year average. Before they break due to their poor branch angles they often show iron deficiency. That's what your one leaf looked like (yellowed leaves with dark green veins, later scorching and turning brown). It is usually more pronounced at the ends of the branches. Adding iron is not an option in this case because it's usually due to the plant's inability to get iron beyond the decaying internal tissues that form between the pinching trunks and to the leaves. Cotton root rot is its other arch enemy. It attacks many species that are growing in alkaline soils, but pears are its favorite hosts.
DEAR NEIL: There are a vitex and a crape myrtle that bloom about a quarter of a mile from our house. They are where a house burned several years ago. We don't know how they survived the fire. Moving them is out of the question but I'd like to consider starting a plant from each for my garden. How are they propagated?
Both are rooted from cuttings. Take 10 or 15 from each plant. If you have a greenhouse it will help since you want very high humidity as the cuttings form their roots. Crape myrtle cuttings root most successfully when they're taken between mid-May and the end of June. You want soft, new growth for their cuttings. Vitex cuttings may be a little more challenging.
Semi-hardwood cuttings taken during the summer may be better options.
You might also try tip-layering both plants. There are complete directions for all of this at my Web site, www.neilsperry.com http://www.neilsperry.com>, under Most-Asked Questions.
DEAR NEIL: Can I root roses from cuttings?
Yes, so long as you are not violating plant patent laws for a new variety.
Antique roses are all started from cuttings. Details on rooting cuttings are the same as those mentioned in the previous question.
DEAR NEIL: We recently moved into a house with four large cedar trees. Nothing is growing beneath them. I'd like to put a border in under them and cover the ground with rocks. Would that hurt the trees?
It would not hurt the trees. If you have a source for that much attractive stone go for it. Bark mulch might be easier and less expensive. It would also look more natural.
DEAR NEIL: Why do crape myrtles fail to flower or bloom sparingly?
It can be due to excessive shade. Some people still insist of topping their crape myrtles each winter and that will slow their summer flowering for many weeks - to say nothing of what it does to the plants' natural form. They flower best when they are growing vigorously, so adding a high-nitrogen plant food is always helpful. Protect older varieties from powdery mildew.
Finally, if the foliage is also sparse it's also possible that a hard or late freeze might have damaged the trunks themselves.
DEAR NEIL: Our bluebonnet patch has been doing very well. Now, however, clover seems to be overtaking it. What should we do the balance of the summer to be certain we have good bluebonnets next year?
Your bluebonnets, as you no doubt have noted, have gone to seed. Now that the plants are completely browned and out of the picture you can apply a broadleafed weedkiller spray to the clover. Use a pump sprayer and mix in one drop of liquid dishwashing detergent with each tank of spray to help it hold onto the waxy leaves. The clover will die away within a couple of weeks. Do not use this near desirable non-grassy plants, however, and do not use that sprayer for insecticides in the future. Mark it for use with herbicides only.
DEAR NEIL: We are having a terrible time with webworms. What is the best way to eliminate them?
Use a long-handled pole pruner to remove the webs when they are quite small.
If they have engulfed entire branches use a hook to break them open. Sprays are not efficient. They are more cosmetic than harmful.
DEAR NEIL: What would cause big juniper trees to die? It appears to start on one side, but neighbors have lost entire trees.
It could be spider mites. Thump some of the declining twigs over white paper to see if you see nearly microscopic mites moving about. Kelthane is the best miticide. It could also be leftover damage from the several years of intense drought, and junipers will also brown and die when they shade one another. If those don't hit it you might want to hire an arborist for an on-site visit.
It could be spider mites. Thump some of the declining twigs over white paper to see if you see nearly microscopic mites moving about. Kelthane is the best miticide. It could also be leftover damage from the several years of intense drought, and junipers will also brown and die when they shade one another. If those don't hit it you might want to hire an arborist for an on-site visit.
DEAR NEIL: Enclosed is a leaf from a Bradford pear near our house. At first the tree was dark green and flowered well but now the leaves are all yellow and there have been no blooms. What can we do to turn it around?
Bradford pears have short life expectancies - generally in the 8- to 10-year average. Before they break due to their poor branch angles they often show iron deficiency. That's what your one leaf looked like (yellowed leaves with dark green veins, later scorching and turning brown). It is usually more pronounced at the ends of the branches. Adding iron is not an option in this case because it's usually due to the plant's inability to get iron beyond the decaying internal tissues that form between the pinching trunks and to the leaves. Cotton root rot is its other arch enemy. It attacks many species that are growing in alkaline soils, but pears are its favorite hosts.
DEAR NEIL: There are a vitex and a crape myrtle that bloom about a quarter of a mile from our house. They are where a house burned several years ago. We don't know how they survived the fire. Moving them is out of the question but I'd like to consider starting a plant from each for my garden. How are they propagated?
Both are rooted from cuttings. Take 10 or 15 from each plant. If you have a greenhouse it will help since you want very high humidity as the cuttings form their roots. Crape myrtle cuttings root most successfully when they're taken between mid-May and the end of June. You want soft, new growth for their cuttings. Vitex cuttings may be a little more challenging.
Semi-hardwood cuttings taken during the summer may be better options.
You might also try tip-layering both plants. There are complete directions for all of this at my Web site, www.neilsperry.com http://www.neilsperry.com>, under Most-Asked Questions.
DEAR NEIL: Can I root roses from cuttings?
Yes, so long as you are not violating plant patent laws for a new variety.
Antique roses are all started from cuttings. Details on rooting cuttings are the same as those mentioned in the previous question.
DEAR NEIL: We recently moved into a house with four large cedar trees. Nothing is growing beneath them. I'd like to put a border in under them and cover the ground with rocks. Would that hurt the trees?
It would not hurt the trees. If you have a source for that much attractive stone go for it. Bark mulch might be easier and less expensive. It would also look more natural.
DEAR NEIL: Why do crape myrtles fail to flower or bloom sparingly?
It can be due to excessive shade. Some people still insist of topping their crape myrtles each winter and that will slow their summer flowering for many weeks - to say nothing of what it does to the plants' natural form. They flower best when they are growing vigorously, so adding a high-nitrogen plant food is always helpful. Protect older varieties from powdery mildew.
Finally, if the foliage is also sparse it's also possible that a hard or late freeze might have damaged the trunks themselves.
DEAR NEIL: Our bluebonnet patch has been doing very well. Now, however, clover seems to be overtaking it. What should we do the balance of the summer to be certain we have good bluebonnets next year?
Your bluebonnets, as you no doubt have noted, have gone to seed. Now that the plants are completely browned and out of the picture you can apply a broadleafed weedkiller spray to the clover. Use a pump sprayer and mix in one drop of liquid dishwashing detergent with each tank of spray to help it hold onto the waxy leaves. The clover will die away within a couple of weeks. Do not use this near desirable non-grassy plants, however, and do not use that sprayer for insecticides in the future. Mark it for use with herbicides only.
DEAR NEIL: We are having a terrible time with webworms. What is the best way to eliminate them?
Use a long-handled pole pruner to remove the webs when they are quite small.
If they have engulfed entire branches use a hook to break them open. Sprays are not efficient. They are more cosmetic than harmful.
DEAR NEIL: What would cause big juniper trees to die? It appears to start on one side, but neighbors have lost entire trees.
It could be spider mites. Thump some of the declining twigs over white paper to see if you see nearly microscopic mites moving about. Kelthane is the best miticide. It could also be leftover damage from the several years of intense drought, and junipers will also brown and die when they shade one another. If those don't hit it you might want to hire an arborist for an on-site visit.
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