E.C.M. Landscaping, Inc.
Example of a abiotic root problem, in this case circling or "bound" roots, which can cause yellowing of evergreens.
It's true that deer densities - even in relatively urban Essex County - are increasing rapidly. This is due to a lack of natural predators and ample food. The suburban landscape is the equivalent of an all-you-can-eat buffet to a deer. The only apparent control on population growth is collision with car bumpers, which we don't recommend. This means your landscape may need to be protected in other ways.
Deer damage landscape plants in 2 main ways: browsing and rubbing. Rubbing is mechanical damage not he trunks and branches of woody plans caused by male deer rubbing their antlers to stake out territory. The result is often broken branches or branches and trunks with the bark scraped off of them. Browsing is the eating the tender shoots of both woody and herbaceous plants.
There is usually no single solution or panacea for deer damage. It usually involves multiple control strategies. Fencing to exclude the deer from your landscape is one options. Deer repellant sprays are another. Selecting plants that are less palatable to the deer is also a possibility. Most situations require a combinations of all three strategies. Factors such as cost and practicality will determine which methods to use in each individual case.
Dry shady areas are harsh environments for plants. Often the reason they are dry and shady is because of large trees nearby which means here there is likely to be extensive root competition too. This limits the possibilities to very tough plants. One such selection is Russian arborvitae - Microbiota decussata. As is often the case, the common name is misleading. It is not an arborvitae, it is in the cypress family.
Microbiota is a small, ground cover type evergreen with scape like foliage reminiscent of some junipers. It can grow up to a foot high (usually lower) and 4-6' across. The foliage is generally soft but a tad prickly. It does not flower noticeably. The foliage is green in spring and summer but fades to a dark purply or even brownish greening late fall and winter. Since it is a cypress it has very few insect of disease problems. Most important is its toughness and ability to complete in those dry, shady conditions.
Yellowing of the foliage of evergreens could be caused by one or more of a great many reasons. Evergreens are generally split into 2 types: broadleaf and conifer. Both types - and each species within each type - have unique soil and site requirements. If the needs of the plant are not being met it will begin to show symptoms of a disorder. Yellowing might be one such symptom.
Some causes of yellowing are: nutrient deficiency (frequently iron or nitrogen) soil pH problems (usually too high), biotic or abiotic root problems (circling roots or "root bound" plantings), fungal diseases, and insect activity. You will need a horticulture professional to evaluate the plants and the site to determine the probable cause. On a positive note, some evergreens such as Aucuba 'Gold Dust' and Crisppsii Hinoki Cypress are naturally yellowish and their golden hues can be used as a focal point or feature in a well designed garden.
If you want a quote from a landscape designer, contact us.