Brown leaves on trees - Ask Extension
Hello , the leaves on my trees {not sure the type of trees} are getting brown . Wondering if they are dying or is there anything I can do?Thank you...
Knowledgebase
Brown leaves on trees #656838
Asked June 27, 2020, 2:40 PM EDT
Hello , the leaves on my trees {not sure the type of trees} are getting brown . Wondering if they are dying or is there anything I can do?Thank you
Seida
Anne Arundel County Maryland
Expert Response
Hello Seida,
These are Leyland Cypress (xCupressocyparis leylandii), a commonly-used evergreen in our area, though one prone to multiple problems. These have been pruned severely (not a recommended practice for long-term health) and the browning could be diseased tissue or merely minor dieback from stress - we cannot see clearly enough to discern which. The mature size of these trees is typically 30 to 40' tall, and they do not replace foliage lost through pruning the way a holly or boxwood can. That means that old wood like this has less and less ability to send out new growth as the tree ages and pruning continues.
Given their current condition and unsuitability for this location, replacements are recommended. If you wish to maintain a hedge or trim plants in this planting bed, a broad-leaved evergreen (holly, cherrylaurel, etc.) would be much easier to work with. If you prefer the look of a conifer (needled evergreen, like this one), then there are several narrow Arborvitae and Juniper varieties to choose from, plus various Yews, which are one of the few conifers that tolerate trimming well. The growing conditions of this site as well as challenges like deer browsing will help to narrow-down the list of candidates.
Here is some information on the common diseases of Leyland Cypress and what symptoms to look for (though no fungicides are effective):
https://extension.umd.edu/hgic/topics/why-are-leyland-cypress-trees-turning-brown
https://extension.umd.edu/hgic/topics/seiridium-and-botryosphaeria-canker-leylands-trees
Browning can also be caused by normal shedding of old needles (normally not noticeable on bushy, unpruned plants) and needle loss due to root stress from too much or too little water.
Miri
These are Leyland Cypress (xCupressocyparis leylandii), a commonly-used evergreen in our area, though one prone to multiple problems. These have been pruned severely (not a recommended practice for long-term health) and the browning could be diseased tissue or merely minor dieback from stress - we cannot see clearly enough to discern which. The mature size of these trees is typically 30 to 40' tall, and they do not replace foliage lost through pruning the way a holly or boxwood can. That means that old wood like this has less and less ability to send out new growth as the tree ages and pruning continues.
Given their current condition and unsuitability for this location, replacements are recommended. If you wish to maintain a hedge or trim plants in this planting bed, a broad-leaved evergreen (holly, cherrylaurel, etc.) would be much easier to work with. If you prefer the look of a conifer (needled evergreen, like this one), then there are several narrow Arborvitae and Juniper varieties to choose from, plus various Yews, which are one of the few conifers that tolerate trimming well. The growing conditions of this site as well as challenges like deer browsing will help to narrow-down the list of candidates.
Here is some information on the common diseases of Leyland Cypress and what symptoms to look for (though no fungicides are effective):
https://extension.umd.edu/hgic/topics/why-are-leyland-cypress-trees-turning-brown
https://extension.umd.edu/hgic/topics/seiridium-and-botryosphaeria-canker-leylands-trees
Browning can also be caused by normal shedding of old needles (normally not noticeable on bushy, unpruned plants) and needle loss due to root stress from too much or too little water.
Miri
