Blue Arrow Juniper

Blue Arrow Juniper

(Photo courtesy of NetPS Plant Finder)

Height: 12 feet

Spread: 24 inches

Sunlight:

Hardiness Zone: 3b

Other Names: Colorado Redcedar

Description:

An extremely narrow and upright small evergreen tree, with showy powdery blue foliage and blue berries; adaptable to dry soils, but needs full sun; excellent for color, articulation or screening, makes a curious, almost formal tall evergreen hedge

Ornamental Features

Blue Arrow Juniper has attractive blue foliage. The scale-like leaves are highly ornamental and remain blue throughout the winter. It produces silvery blue berries from late spring to late winter. The flowers are not ornamentally significant.

Landscape Attributes

Blue Arrow Juniper is a dense multi-stemmed evergreen shrub with a narrowly upright and columnar growth habit. It lends an extremely fine and delicate texture to the landscape composition which can make it a great accent feature on this basis alone.

This is a relatively low maintenance shrub, and is best pruned in late winter once the threat of extreme cold has passed. Deer don’t particularly care for this plant and will usually leave it alone in favor of tastier treats. It has no significant negative characteristics.

Blue Arrow Juniper is recommended for the following landscape applications;

  • Accent
  • Vertical Accent
  • Hedges/Screening
  • General Garden Use

Planting & Growing

Blue Arrow Juniper will grow to be about 12 feet tall at maturity, with a spread of 24 inches. It has a low canopy, and is suitable for planting under power lines. It grows at a medium rate, and under ideal conditions can be expected to live for 70 years or more.

This shrub should only be grown in full sunlight. It is very adaptable to both dry and moist growing conditions, but will not tolerate any standing water. It is considered to be drought-tolerant, and thus makes an ideal choice for xeriscaping or the moisture-conserving landscape. It is not particular as to soil type or pH. It is highly tolerant of urban pollution and will even thrive in inner city environments. This is a selection of a native North American species.

Address juniper problems

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Q. Some of the branches have turned brown on my juniper shrubs. I have had these same shrubs for years and they have been getting the same care as always but suddenly they have browning tips and branches dying. Can you tell me what is wrong?

A. Junipers make for hardy trees and shrubs in the landscape as they withstand cold, heat and drought with ease. However, despite their resilience, junipers are prone to a couple of diseases and insect infestation that cause browning. Bagworms, spider mites, and the fungal diseases tip blight or twig blight, may cause the branches and twigs to lose their vibrant green color.

The symptoms of branches turning brown could be caused by several things. Browning and dying branch tips may indicate an insect infestation such as spider mites. You can check for this by holding a piece of white paper under a juniper branch and shaking it. Look at any small specks that fall on the paper through a magnifying glass. If you see brown, red, green or yellow eight-legged insects, your juniper has spider mites.

Twigs and branches dying back could indicate juniper tip blight. To control prune out dead tips, making sure to go into the green part of the branch at least 2 inches. Clean pruning shears with 10 percent bleach solution or rubbing alcohol between cuts.

Bad fungal infections can be controlled with copper spray. Junipers need air flow to avoid fungal disorders, so cleaning up around the shrubs and pruning out any dead wood is important. It is also important to keep branches dry during warmer weather, so avoid overhead water or watering too often during the summer.

If the drainage is poor, the plants may develop root rot, causing the whole or parts of the plant to die. I do not think this is the case with your shrubs as you said they have been growing in the same place for years.

Entire branches dying back especially on larger shrubs or juniper trees may be due to twig blight. This is caused by cankers. This disease can also cause foliage on infected branches to turn yellow or brown and wilt. According the UC, IPM site: “A canker is a localized dead (necrotic) area on branches, trunks or roots. Cankers vary greatly in appearance but are often a circular or oblong lesion that may be discolored, oozing or sunken. Cutting under cankered bark usually reveals discolored tissue, which may have a well-defined margin separating it from healthy tissue. When cankers entirely circle (girdle) stems or trunks, foliage turns yellow or brown and wilts as the plant dies outward or upward from the canker.”

Infected bark often discolors and may exude copious resin. If you think you have blight or canker, prune out infected branches, again making sure to clean pruners between cuts. For further information, go to http://www.ipm.ucdavis.edu/PMG/GARDEN/PLANTS/juniper.html.

The Shasta Master Gardeners Program can be reached by phone at 530 242-2219 or email [email protected] The gardener office is staffed by volunteers trained by the University of California to answer gardeners’ questions using information based on scientific research.

Juniper Diseases & Insect Pests

Junipers grown in South Carolina are relatively low-maintenance plants if planted in the correct location and given proper cultural care. There are several common problems that can cause browning of needles and dieback of entire shoots, especially when junipers are improperly planted or under stress from the environment. Avoid many of these problems by selecting resistant varieties, avoiding overhead watering and selecting a planting site with good drainage. More information is available in HGIC 1068, Juniper.

Diseases

Twig & Tip Blight: Junipers frequently exhibit dieback of shoot tips or entire shoots and browning of needles. Needles may drop from the plant, and dark cankers may form at the junction of live and dead wood. This problem occurs typically during warm, wet weather conditions and is usually caused by one of the fungal organisms described below.

Phomopsis blight (Phomopsis juniperovora) on juniper.
Bruce Watt, University of Maine, Bugwood.org

Phomopsis Tip Blight: This disease is caused by the fungus Phomopsis juniperovora and begins by infecting the tips of branches smaller than the diameter of a pencil.

The new, immature growth becomes infected while the darker green, mature foliage remains resistant to infection. Infected twigs first become pale, then turn reddish-brown and finally become brown after death. Scraping away the bark will reveal a sharp line between discolored, dead wood and healthy wood. Watch for disease development during the spring or summer flush of new growth when warm, wet conditions are present.

Cercospora Twig Blight: This disease is caused by the fungus Cercospora sequoiae var. juniperi. It begins by infecting the oldest needles that are located on the lower branches, inside of the plant. As disease development progresses, the needle browning spreads upward and outward. Branch tips usually remain healthy and green. Needles of spur branches turn brown and die usually in the late summer, leaving a plant with an inner crown devoid of foliage. This disease is sometimes confused with mite damage.

Prevention & Treatment: Each of these diseases requires similar methods of control. First, closely inspect the entire plant, since symptoms of tip blight and twig blight can be caused by other problems, such as drought, overwatering or root injury.

Purchase disease-resistant varieties that are healthy with no evidence of dead or dying twigs. Do not stress junipers by planting them in shaded or poorly drained locations. Plant junipers in areas with good air circulation to promote rapid drying of the needles. Do not crowd plants, and avoid using sprinkler irrigation. Promptly prune and remove any diseased or browning branches as they occur. Except on highly susceptible cultivars, pruning will usually control these diseases.

If chemical control is necessary, fungicides are available to provide protection, but they must be applied before infection occurs. Select a fungicide labeled for use on junipers containing one of the following: mancozeb, thiophanate-methyl or copper salts of fatty acids. See Table 1 for examples of products. Apply all chemicals according to directions on the label.

Kabatina Twig Blight: This disease is caused by the fungus Kabatina juniperi. The symptoms are the same as described for Phomopsis tip blight, except this fungus kills older (usually 1-year-old) twigs in the spring. Damaged or stressed tissues are more susceptible to Kabatina twig blight.

Kabatina blight (Kabatina juniperi) on juniper.
Bruce Watt, University of Maine, Bugwood.org

Kabatina blight (Kabatina juniperi).
Bruce Watt, University of Maine, Bugwood.org

Cedar-apple rust (Gymnosporangium juniperi-virginianae) on Eastern red cedar.
Linda Haugen, USDA Forest Service, Bugwood.org

Cedar-Apple Rust: This fungal disease of apple, crabapple and Eastern red cedar is caused by several species of Gymnosporangium. The disease not only affects Juniperus species including Eastern red cedar (Juniperus virginiana) but requires another host plant, apple or crabapple, to complete its life cycle. This disease spreads from junipers to the apple and then back to juniper. It can be a severe problem wherever these two are grown together. Eastern red cedar is the most commonly infected juniper.

On juniper, hard, brown, up to 2-inch diameter galls form near the ends of the branches in the summer. In the spring following a rain, the galls produce large, orange, gelatin-like tendrils, full of spores, which can blow a half-mile to infect nearby apple and crabapple trees.

Symptoms that occur on the apple trees appear as yellow spots on the upper leaf surface. In the late summer, these yellow spots form spores that are spread to the leaves and twigs of nearby junipers (within 2 miles) to infect them.

Prevention & Treatment: Select resistant varieties of apple (such as ‘Enterprise’, ‘Pristine’, ‘Liberty’ or ‘Redfree’) or juniper. Prune out all galls on the juniper, if possible. Do not plant apple, crabapple and Eastern red cedar trees in the same area. If disease is severe enough to warrant control, or a particular specimen plant is affected, select a fungicide containing mancozeb or propiconazole. See Table 1 for examples of products. Do not use fruit for food if propiconazole products are used. Apply all chemicals according to directions on the label. More information is available in HGIC 2000, Apple and Crabapple Diseases.

The following Juniper varieties are Generally Resistant to Phomopsis Twig Blight & Cedar Rusts:

  • Juniperus chinensis – Chinese Juniper
  • ‘Foemina’
  • ‘Keteleeri’
  • ‘Mint Julep™’
  • ‘Pfitzeriana’
  • var. sargentii (Sargent Juniper)
  • J. communis – Common Juniper
  • ‘Aureospica’
  • ‘Suecica’
  • J. squamata – Singleseed Juniper
  • var. fargesii
  • J. sabina – Savin Juniper
  • ‘Broadmoor’
  • ‘Skandia’
  • J. virginiana – Eastern Red Cedar
  • ‘Tripartita’
  • J. horizontalis – Creeping Juniper
  • ‘Tripartita’
  • ‘Wiltoni’ (‘Blue Rug’)
  • ‘Plumosa’

Phytophthora Root Rot: This root rot is one of the most serious and difficult-to-control fungal diseases that affects a wide range of plants in South Carolina. It is caused by a soil-borne fungus, Phytophthora cinnamomi, and the most common symptom is the slow decline of the plant. Leaves on the plant will become thin or sparse. Some plants may die one branch at a time, until the entire plant dies. The centers of the roots change from white to reddish-brown and the outer layer of the roots separates easily from the core. High soil moisture and warm soil temperatures favor disease development.

Prevention & Treatment: It is important to prevent this disease by cultural methods, since chemical treatment is ineffective once symptoms are noticed. Avoid planting in poorly drained areas where Phytophthora root rot thrives. Heavy clay soils, areas that flood and sites where runoff water is a problem typically create root rot problems. Plant junipers in raised beds, except in deep sandy soils. If you must plant in a site that has heavy clay or does not have good internal drainage, amend the site by thoroughly mixing a porous material, such as ground pine bark (not sawdust or peat), into the bed to a depth of 8 to 12 inches.

Avoid varieties that are the most susceptible to root rot. Some highly susceptible junipers that are likely to be killed by the root rot fungus include: ‘Andorra,’ ‘Bar Harbor,’ ‘Parsoni,’ ‘Sargents,’ ‘Shore’ and Juniperus procumbens ‘Nana.’

Fungicides can be effective on a preventative basis only, and repeat applications are required. Fungicides containing mefenoxam (Subdue GR) can be applied in the home landscape to suppress disease, but it will not cure an infected plant. Due to product cost and for accurate application, homeowners may want to hire a licensed landscaper to apply products containing these fungicides. Apply all chemicals according to directions on the label.

Insects & Other Pests

Bagworm pupae (Thyridopteryx ephemeraeformis).
Gerald J. Lenhard, Louisiana State University, Bugwood.org

Bagworm: Bagworm (Thyridopteryx ephemeraeformis) infests many shrubs and trees, but conifers (evergreens) are the preferred hosts. Damage to plants results from feeding by the caterpillar, which causes loss of leaves. Mild infestations of this pest slow the growth of junipers. Heavy infestations can kill a plant.

The adult male is a dark-colored, hairy moth with a 1-inch wingspan and clear wings. The adult female is yellow and appears almost maggot-like. The larva (immature form or caterpillar) produces a carrot-shaped bag that it carries with it as it feeds. The bag is formed from silk that the larva produces. As it feeds, the larva adds bits of plant material to the bag. The bag is about 2 inches when complete.

In South Carolina, bagworms survive the winter as eggs in a bag. The larvae hatch during May. They spin their cases and carry them along as they feed. After further development, the adult male emerges from its bag in late summer. It locates an adult female in her bag. After mating, the female lays 500 to 1,000 eggs in her bag and dies.

Prevention & Control: Several parasites and predators feed on bagworms, generally keeping their numbers under control. Removal of the egg-containing bags during winter and early spring is a very effective method for preventing problems before the next growing season. Once removed, the bags should be destroyed or placed in a deep container, which allows beneficial parasites that may also be present in the bags to escape while retaining the bagworm larvae.

If the infestation is severe or the bags are out of reach, spray with the bacterial insecticide Bt. This insecticide contains spores of the bacterium, Bacillus thuringiensis, which when eaten kill the caterpillar. Young larvae are much more susceptible to the treatment than are older larvae. As such, apply this pesticide in the spring as soon as bagworms are seen. Control is most effective when spraying is done in late afternoon or early evening. See Table 1 for examples of products containing Bt. This insecticide is very safe to use. As with any pesticide, read and follow all label directions and precautions before using.

Spruce Spider Mite: Mites are not insects but are more closely related to spiders. Spruce spider mites (Oligonychus ununguis) are serious pests of juniper. They are very small and not seen easily with the naked eye. They have piercing mouthparts that they use to suck plant sap. Their feeding results in speckling (formation of tiny yellow spots) on needles. Some needles may turn brown and drop off. With heavy infestations, fine webbing may be seen on the plant. Several seasons of heavy mite feeding may kill a juniper. Although most spider mites increase in numbers during hot, dry weather, spruce spider mites are cool-weather mites. Their population peaks during spring and fall, but drops dramatically during the heat of summer when predators feed on them.

Control: Naturally occurring enemies of mites include various predator mites, ladybird beetles (ladybugs) and other insects. These predators will usually suppress mite populations. Since insecticide use kills beneficial predators as well as mites, insecticides should be avoided unless absolutely necessary. Misuse of insecticides can result in increased problems with mites by causing the death of natural predators of the mite. Miticides, labeled specifically for mite control, are less harmful to beneficial insects. Mites can be removed with a strong spray of water, if applied on a regular basis.

To determine whether insecticide use is needed, it helps to know how many mites are present. Hold a white sheet of paper under a branch and strike the branch. The mites that are knocked off will be seen crawling around on the paper. If dozens of mites are seen per whack, serious damage can result. Continue to check population numbers at seven to ten day intervals. Pesticides labeled for homeowner use against spruce spider mites include insecticidal soaps or horticulture oil sprays. See Table 1 for examples of products. As with any pesticide, read and follow all label directions and precautions before using.

Juniper Scale (Carulaspis juniperi).
Joseph La Forest, University of Georgia, Bugwood.org

Juniper Scale: Symptoms of juniper scale (Carulaspis juniperi) infestation are very similar to symptoms of spruce spider mite infestation. Initially, the juniper appears off-color and infested branches show little growth. The needles eventually turn yellow or brown. Branches may die back. If ignored, juniper scale infestation may kill the plant in two to three growing seasons. Signs of the pest include clusters of tiny bumps or scales about 1/8-inch in diameter, especially on the undersides of needles. Adult females are white at first but turn gray or black later. Adult females are mostly flat with a slight volcano appearance, if viewed through a magnifying lens. In addition, a shiny, sticky material (honeydew) is often seen on needles of junipers infested with juniper scale.

Juniper Scale (Carulaspis juniperi).
United States National Collection of Scale Insects Photograph Archive, USDA Agriculture Research Service, Bugwood.org

Adult females survive the winter on the plant. In early spring, they lay eggs under their shell. The immature forms, called crawlers, hatch and crawl around before settling on the needles to feed. They feed by sucking plant sap. As they mature, they form a crusty shell over their bodies. Their legs become useless and they remain in one location. As they feed, excess sap is excreted as a sugary material, called honeydew. The sooty mold fungus can grow on the honeydew, forming dark splotches on needles.

Control: The presence of adults or crawlers determines which treatment will be most effective. Use a 2 or 3% horticultural oil mix as a dormant spray in late winter or very early spring before new growth occurs to control adult females by suffocation. A 2% solution is made with 5 tablespoons of horticultural oil per gallon of water. See Table 1 for examples of products.

Most insecticides are effective only against the crawlers. Monitor the crawler emergence with sticky cards, double-faced tape wrapped around a branch, or by putting an infested shoot into a baggie and watching for crawler movement. Crawler activity often coincides with the flush of new plant growth in the spring. However, some scale species may have overlapping generations with an extended crawler emergence period, such as along the coast. Insecticides recommended for use against crawlers include acephate, malathion, and cyfluthrin . See Table 1 for examples of products. Read and follow all label directions and precautions before using.

Other Problems

Needle Browning: These symptoms appear as needles that initially turn yellow, then brown and dry, before finally dropping from the plant. These symptoms can occur inside the plant nearest the trunk, on the tips or scattered throughout the plant. The entire plant may die if the condition is severe enough. There are many conditions that will cause needles to turn brown on junipers, including many diseases already discussed. A few reasons needles may turn brown are described below.

Drought & Overwatering: These two problems cause similar symptoms on junipers. Check to see if the ground is dry or frozen. Overwatering causes the plant’s root to rot, therefore rendering it unable to take up water.

Dog Urine: Salts in the urine burn the foliage causing it to appear scorched. Rinse the foliage if you suspect this is a problem.

Note: Control of diseases and insects on large trees is usually not feasible, since adequate coverage of the foliage with a pesticide cannot be achieved.

Table 1. Insecticides & Fungicides to Control Juniper Insect Pests & Diseases.

Insecticides & Fungicides Examples of Brand Names & Products
Acephate Bonide Systemic Insect Control Concentrate
Bacillus thuringiensis (Bt) Bonide Thuricide Concentrate
Garden Safe Bt Worm & Caterpillar Killer Concentrate
Natural Guard Caterpillar Killer Spray with Bt Conc.
Safer Caterpillar Killer Concentrate
Southern Ag Thuricide Bt Caterpillar Control
Tiger Brand Worm Killer Concentrate
Monterey Bt
Copper Fungicides Bonide Copper Fungicide Spray or Dust
Bonide Liquid Copper Concentrate
Camelot O Fungicide/ Bactericide Concentrate
Monterey Liqui-cop Fungicide Concentrate
Natural Guard Copper Soap Liquid Fungicide Conc.
Southern Ag Liquid Copper Fungicide
Cyfluthrin Bayer Advanced Vegetable & Garden Insect Spray Conc.
Horticultural Oil Bonide All Seasons Spray Oil Concentrate
Ferti-lome Horticultural Oil Spray Concentrate
Southern Ag ParaFine Horticultural Oil Concentrate
Monterey Horticultural Oil Concentrate
Summit Year Round Spray Oil Concentrate
Insecticidal Soap Bonide Insecticidal Soap Concentrate
Safer Brand Insect Killing Soap Concentrate
Natural Guard Insecticidal Soap Concentrate
Garden Safe Insecticidal Soap Insect Killer Concentrate
Espoma Earth-tone Insecticidal Soap Concentrate
Malathion Bonide Malathion 50% Insect Control
Gordon’s Malathion 50% Spray
Hi-Yield 55% Malathion Insect Spray
Martin’s Malathion 57% Concentrate
Ortho Max Malathion Insect Spray Concentrate
Spectracide Malathion Insect Spray Concentrate
Southern Ag Malathion 50% EC
Tiger Brand 55% Malathion
Mancozeb Bonide Mancozeb Flowable with Zinc Concentrate
Southern Ag Dithane M-45
Propiconazole Banner Maxx Fungicide
Bonide Infuse Systemic Disease Control Concentrate
Ferti-lome Liquid Systemic Fungicide II Concentrate
Thiophanate Methyl Cleary’s 3336-WP Turf & Ornamental Fungicide
Southern Ag Thiomyl Systemic Fungicide

Blue Arrow Juniper

The Blue Arrow Juniper, (Juniperus scopulorum ‘Blue Arrow’) is a sun-loving, narrow, upright evergreen with powdery blue foliage. This plant is a best seller for us because people just love tall, skinny evergreens.

They create a beautiful privacy screen without taking up your whole yard. This is a colorful addition to your landscape with tight, bright blue foliage.

Everyone loves the intense silvery blue foliage of this Juniper. It is a cultivar of a native North American Rocky Mountain Juniper that was selected for the narrow upright form.

This tree gives you a vertical accent with a very delicate fine-textured foliage. Blue Arrow also produces silvery blue berries from late spring on and the birds love them.

Deer don’t like the taste of these small trees, but the birds will flock to Blue Arrow Junipers from spring to late winter. They will take shelter in them and eat the berries as a welcome food source.

You’ll get cool blue color year round and rugged cold hardiness. These pretty trees are even tough enough to handle urban pollution.

They’ll act as a wonderful windbreak or visual barrier. Did we mention the deer leave them alone?

For some great structural shape and unique color in your garden, pick up a few from Nature Hills today!

How to Use Blue Arrow Juniper in the Landscape

If you want an exclamation point to spotlight the entrance to your home, gate or the start of a path, use this evergreen as a “sentinel”. Use these to welcome guests to a special Outdoor Room.

One can be very effective by itself, but it’s really fabulous when two are planted as a pair, flanking either side of an entrance.

Have a tight corner in a side yard, or along a driveway with a view you want to hide? Plant several as a tall, narrow screen where space is limited.

Blue Arrow makes a fun and skinny 15-20 foot tall hedge that only gets about 3-4 feet wide – perfect for those sunny sites where room is limited. Measure 3 feet from the middle of one trunk to the next trunk when planting as a screen.

They can be sheared to keep a particular size, but why not allow them to grow naturally with their pretty, soft and fluffy look? If you do trim this Juniper, it will tend to get a bit wider, so keep that in mind.

This tree may be the perfect background for beds, so consider planting several in a gentle curve at the back of your garden border. It will work to provide gorgeous definition. The silvery blue color will work beautifully with a very wide perennial plant color palette.

The growth habit is sophisticated enough to handle an upscale setting, but the soft texture works just as well in a rustic landscape. It’s all in the styling with this plant.

Have you ever been out to Las Vegas? Have you seen the way they use Italian Cypress in front of Ceaesar’s Palace? Gardeners in colder growing zones can use this tree to replicate that look.

This kind of formal, skinny growth habit can also be used very effectively in a modern landscape.

Plant several as a tall, narrow screen where space is limited. Measure 3 feet from the middle of one trunk to the next trunk when planting as a screen.

No matter how you use it, you’ll truly appreciate the way this plant gives you year round interest.

#ProPlantTips for Care

To get your plant’s root system established, give Blue Arrow Juniper regular deep water. However, with this variety, you’ll want to be careful not to overwater. Once your plants are rooted in, they will seldom need additional moisture except in the warmer climates.

There are only two things that Blue Arrow demands: full sun and well-drained soil. With only those two requirements, the plant is a no-brainer to grow.

Order enough of these low-maintenance winners to complete your project today!

Dying limbs on blue arrow junipers

Dennis,
I am sorry to learn that you are having trouble with your junipers. Evergreens do naturally lose some needles, but the browning shown in your photos does not look normal. There are several possibilities for the needle problems.
Since the garden center staff suggested the possibility of spider mites, let’s begin with mites. Spruce spider mites do attack junipers. Unfortunately from the photos I can’t determine if spider mites are the problem. The following website provides a very good description of how to determine if your junipers have spider mites. The populations of spruce spider mites build in the fall, so you should begin looking for them now and during the next several weeks.
http://aces.nmsu.edu/ces/yard/1998/030998.html
The following website has some good photos.
http://woodypests.cas.psu.edu/FactSheets/InsectFactSheets/html/Spruce_Spider_Mite.html
If you do find signs of spider mites the first thing to try is a sharp spray of water that will dislodge the pest. If possible you want to avoid using pesticides because they will also kill the beneficial insects that keep the mites under control. The lady beetle you spotted is a beneficial insect. I am assuming the spider you saw is also a beneficial and not a spider mite. Spider mites are very small, and the web does not look like a traditional spider web (see the above website for a photo of spider mite webbing).
You also want to be sure the junipers are getting adequate water. A water stressed plant is more susceptible to mites. I realize that during part of this summer we have been receiving ample rain, but more recently there have been longer stretches of dry weather. You want the soil to remain moist but not soaking wet.
The Bayer 3 in 1 product will kill spider mites, but it will also kill many other insects. I would use this product only if you are sure you have spider mites and all other management strategies have failed.
In addition to spider mites there are several other pests that could be causing the browning. The following website contains a list of potential spruce problems and some photos. Possibly you can use this information to diagnose your problem.
http://www.clemson.edu/extension/hgic/pests/plant_pests/shrubs/hgic2056.html
The problem could also be related to cultural practices. You mentioned that the junipers have not received supplemental water this year. What about last year? Last summer was very dry. Lack of supplemental water may have contributed to the problem.
Is it possible that a herbicide was sprayed on the plants?
From the photos it looks like the mulch is touching the trunks of the shrubs. I don’t think this is causing your problem, but it is best to keep the mulch a few inches away from the base of the plant.
You mentioned that you did not fertilize this year. That is good. You don’t want to fertilize a stressed plant. Once the problem is managed you can fertilize based on the results of a soil test. In many cases trees and shrubs do not need fertilizer, and over-fertilization can cause problems. For this reason it is important to follow the recommendations of your soil test. If you have not soil tested the area within the last 3 years, you can obtain a soil test kit from the MSU Bookstore. The following is the website for purchasing the test kit.
http://bookstore.msue.msu.edu/product/soil-test-kit-selfmailer-1116.cfm
Diagnosing plant problems can be difficult. If you have looked at all of the above information and cannot determine the exact cause of the problem, you have several options.
You can bring a sample into the Michigan State University Extension-Oakland County Hotline, located in Pontiac. At this time of year it is a good idea to call before going because hours are seasonal. The telephone number is 248-858-0902. The technicians can also tell you the size of sample to bring. There is a $5 dollar charge.
Another option is sending a sample to the diagnostic lab on the MSU campus. The website for the lab is
http://www.pestid.msu.edu/
Another option is a consultation with a certified arborist. An arborist will come to your property and can evaluate the plants, the planting methods and the environment. Some arborists will do an initial consultation at no cost. You can find a certified arborist in Oakland County at the following web site. Once at the site, select “find a tree care service” from the menu at the top of the page. You can then enter your postal zip code, and a list of certified arborists will be provided.

I hope this information is helpful. Please reply back if you have additional questions. Thank you for using our service.

Blue Arrow Juniper

Blue Arrow Juniper

(Photo courtesy of NetPS Plant Finder)

Height: 15 feet

Spread: 4 feet

Sunlight:

Hardiness Zone: 4a

Other Names: Colorado Red Cedar

Description:

An extremely narrow and upright small evergreen tree, with showy powdery-blue foliage and blue berries; adaptable to dry soils, but needs full sun; excellent for color, articulation or screening, makes a curious, almost formal tall evergreen hedge

Ornamental Features

Blue Arrow Juniper has attractive blue foliage. The scale-like leaves are highly ornamental and remain blue throughout the winter. It produces silvery blue berries from late spring to late winter. The flowers are not ornamentally significant.

Landscape Attributes

Blue Arrow Juniper is a dense multi-stemmed evergreen shrub with a narrowly upright and columnar growth habit. It lends an extremely fine and delicate texture to the landscape composition which can make it a great accent feature on this basis alone.

This is a high maintenance shrub that will require regular care and upkeep, and is best pruned in late winter once the threat of extreme cold has passed. Deer don’t particularly care for this plant and will usually leave it alone in favor of tastier treats. It has no significant negative characteristics.

Blue Arrow Juniper is recommended for the following landscape applications;

  • Accent
  • Vertical Accent
  • Hedges/Screening
  • General Garden Use

Planting & Growing

Blue Arrow Juniper will grow to be about 15 feet tall at maturity, with a spread of 4 feet. It has a low canopy, and is suitable for planting under power lines. It grows at a medium rate, and under ideal conditions can be expected to live for 70 years or more.

This shrub should only be grown in full sunlight. It is very adaptable to both dry and moist growing conditions, but will not tolerate any standing water. It is not particular as to soil type or pH. It is highly tolerant of urban pollution and will even thrive in inner city environments. This is a selection of a native North American species.

Gertens Sizes and Prices

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