Question
I planted a row of Arborvitae trees 4 years ago and all were doing well up until a month ago. One is completely dead and the one next to it is turning brown also. I think they have had enough water. There has been no sprays or any other chemicals on or around them. I don't know what to do. It doesn't look like they have any sort of insects on them either. My Mother has also lost 4 of her Blue Spruce trees this year. Hers have a sort of growth on the tips that look sort of like a pine cone growing, but they have a worm in them. Can you help us?
thanks,
Carol

Answer
Hi there: You will probably need to call an arborist.I have enclosed a rather lengthy report of many of the factors that cause your decline problem,hope you don't fall asleep. lol
I will tell you what is on the end of your Mom's spruces 1st  Cooley Spruce Galls:
   * Cooley spruce galls are common and conspicuous on blue spruce. However, they do little or no harm to the tree.
   * The galls are produced by aphid-like Insects, Cooley spruce gall adelgids.
   * Cooley spruce gall adelgids require two hosts to complete their normal life cycle: spruce and Douglas-fir.
   * Once the galls begin to form, insecticides usually are ineffective because the Insects are protected within the galls.
   * The best times to spray are in the spring before new growth starts or in the fall when overwintering stages of the insect have returned to the tree.
Control of Cooley spruce gall is rarely needed to protect tree health. Infestations of this insect are highly cyclical, with their numbers often changing greatly from season to season. However, Insects may be controlled to prevent aesthetic injuries that can detract from tree appearance.
Control must occur before galls begin to form. Apply treatments in fall, after the overwintering females have settled on the plants, or, most commonly, in spring. Spring applications are most effective if made before the Insects have begun to swell with eggs, which typically occurs in late April.
Foliar treatments of carbaryl (Sevin) and permethrin have been most effective.

Dying Cedar Hedges?br> What Is The Cause?
Dieback of cedar hedging in the landscape is a common problem. In most cases, it抯 not possible to pinpoint one single cause. Death is usually the result of a combination of environmental stresses, soil factors and problems originating at planting.
Disease, insect or animal injury is a less frequent cause.
Identifying the Host
Certain species of cedar are susceptible to certain problems, so identifying the host plant can help to identify the cause.
The most common columnar hedging cedars are (Western Red Cedar) and (American Arborvitae or Eastern White Cedar).
Both species are often called arborvitae.
Symptoms
Trees often die out in a group or in one section of the hedge. If they are stunted compared to healthy trees, this is an indication that they have been under stress and declining for several years, probably since the original planting. If death has occurred
Suddenly, with no previous symptoms, then consider some change or extreme condition that might have happened in the recent growing season. Note whether entire trees have been killed or just a few scattered branches. If entire Trees are dead; this suggests damage to the roots and/or base of the tree.
Planting Problems
Roots fail to grow out of the root ball sufficiently after planting. Trees that survive the first year after transplanting may remain stunted and decline gradually for several years, until another stress results in tree death.
Common causes of root growth failure is:
Desiccation: In hot summer weather, root balls can easily dry out in the truck or at the site before the trees are transplanted. This prevents new root growth. When dead trees are dug up, a dry air space can often be found between the root ball and the side of the planting hole. Plant new hedges in cool weather and keep roots moist. Balled and burlapped  plants are more susceptible to desiccation than plants grown in containers, since up to 90% of their root system is lost at digging.
Twine and Burlap: Some twine may not disintegrate quickly enough in the soil. If the twine is not removed at planting, it may cut into the stem as it grows, causing decline and death of the tree. Some burlap sacking is treated with copper sulfate to prevent rot. This gives the burlap a blue or green color. If treated burlap is not removed before planting, the copper sulfate can prevent new root
Growth. (Untreated burlap will rot quickly in soil and does not need to be removed before planting.)
Girdling: If the root ball has become pot bound in a nursery container and is not cut and spread open at planting, the taproot
may grow around the base of the stem and gradually kill the tree. Root girdling can be seen when dead trees are dug.
Excess Fertilizer: Can cause root burn from high salts. Trees will show symptoms of yellowing or nutrient deficiency
and brown up entirely if new roots do not form. Death usually occurs in the first year after transplanting. A layer of fertilizer is often found in the root zone.
Soil Type and Compaction: If the soil at the planting site is quite different from the soil in the Root ball, new roots may have difficulty growing into it. This is particularly true where the landscape soil has high clay content or is compacted from construction.
Planting Too Deep: Roots die out from lack of oxygen. Trees brown up in the first growing season, as from desiccation or fertilizer burn.
Physiological Effects
Flagging/Browning: If only a few branches have died out in patches along the hedge in summer, this may be natural cedar flagging. It is very common on Western Red Cedar and less frequent on Eastern White Cedar. Flagging may be more severe in hot,dry weather but is not considered harmful to the tree.
Discolored Foliage: Foliage may take on a bronze to reddish brown to black color in cold winters. This is natural and the trees will green up as the growing season progresses. A few varieties have a natural bronze or blue tinge in certain seasons. Some cedars appear blue when flowering.
Environmental, Soil And Chemical Factors
Heat: Foliage can become dull or bronzed in midsummer from heat and desiccating winds.
Water Stress: Cedars are relatively shallow-rooted trees. They are susceptible to drought stress especially on well drained, sandy soils. The extreme of very wet conditions in the fall and winter, followed by a hot, dry summer, is very stressful for the roots. Hedges should be watered during very dry periods. Mulching will also help to maintain even soil moisture and temperature.
Prolonged flooding and over watering can also cause root death from lack of oxygen in the soil. Water can accumulate under hedges that are planted downhill from watered lawns. Watering with sprinklers that are timed to go on at short intervals every day will keep the soil continually wet and promote shallow rooting. It is preferable to water deeply for about 30-40 minutes, 2 or 3 times per week.
Compaction: After a few years of healthy growth, a hard pan or clay layer in the subsoil may restrict roots, resulting in stunted trees, greater susceptibility to water stress and gradual decline. A hard or clay layer can often be found when the dead tree is dug
Up.
PH: Thuja prefers a soil pH of 6 to 6.5, but will grow well in soils up to 7.5. Soils that are too acid can result in nutrient deficiency symptoms (browning or yellowing of foliage) and eventual tree decline. Apply dolomitic lime to increase the pH of acid soils.3
Fertilizer: Root burn from excess fertilizer is a common problem, especially at the end of the hedge or at a corner, where the applicator may have stopped or turned. Root burn will cause foliage to brown off and may kill the tree if severe.
Herbicide: Runoff or drift from herbicides may injure cedar hedges. It may take a year for an entire tree to gradually die after exposure to a systemic herbicide, such as ROUNDUP?
Road Salt: Road salt can damage foliage if slush splashes up onto trees. It can also kill roots by accumulating under hedges in melt water or runoff.
Mechanical: Injury to the base of trees from mowers and trimmers.
Insect, Disease and Animal Agents
Cypress Tip Moth: Larvae tunnel into leaf scales on one and 2 year-old twigs in the spring. Leaves become yellow, then brown in late winter. White, spun cocoons can be found on leaf scales in early
June. Western Red Cedar is not affected.
Root Weevil: Adult weevil feeding can girdle young twigs and turn foliage brown, similar to flagging. The weevils feed at night so are not usually seen. Notching of the stem will be evident below the flagged portion of the branch. Damage can occur from March to July. If there is a lot of damage, a sticky band around the trunk will prevent adult feeding. Larvae may feed on roots but do not generally damage trees once past the seedling stage.
Mites: Overall yellowing or browning of foliage in summer may be due to desiccating winds and drought stress or to mites. A few mites are not usually a problem, but in hot, dry weather they can build up to damaging levels. A magnifying glass may be needed to see them. Apply a specific miticide for control.
Juniper Scale: Juniper scales attack juniper, arborvitae, cedar and cypress. Cones, twigs and needles are attacked. Heavy infestations deplete plant sap resulting in grey or yellow foliage, reduced growth over time and possible death of young trees.
Black sooty mold often develops on honeydew.
Scales are round to oval, white and 1.5 mm long. Direct controls against the newly-hatched crawlers in mid-June.
Mice and Rodents: Chewing injury can often be found on twigs just below dead leaves. Damage is often worse at the base of the tree, but can occur quite high up. Bark can also be chewed or stripped off at the base of the tree. This may cause death of the branches on one side, or, if the trunk is girdled, may kill the tree entirely. Dogs have also been known to chew lower branches and strip bark from trunks.
Dog Urine: Small yellow, brown or black patches of dead foliage at the base of trees.
Root Rot: Armillaria root rot is sometimes found in cedar hedges and will kill the trees. Fans of white fungal material can be found under the bark at the base of dead trees and in the roots. Black 搒trings?called rhizomorphs spread the fungus from one tree
to another along the hedge. There is no cure for Armillaria. Dead trees should be removed and replaced with a resistant species.
Phytophthora is a weak pathogen on Thuja, invading roots that have been damaged by water stress (drought and flooding) or other factors.
Foliar Blights
Keithia blight caused by a fungus called Didymascella thujina, is the more serious disease of Eastern White Cedar. Infected leaf scales have small, black, circular shot holes and often turn white. Foliage turns brown and drops, leaving branches bare. Small trees and seedlings can be killed entirely but mature landscape trees are less severely affected. On mature trees in dense stands and damp or shaded areas, low branches can appear scorched. Upper branches are less affected. In the landscape, the disease can be controlled with fungicides if necessary. Apply a product containing fixed copper, zineb or mancozeb every 2 weeks from late March to mid-June, especially during wet weather.
Seridium blight, caused by the fungus Seiridium cardinale, occasionally causes twig and foliar dieback and small twig and branch cankers. It is usually a minor or weak pathogen on Thuja.
Kabatina thujae will occasionally cause leaf and shoot death on Eastern White Cedar.
Hope you are still awake,Bill