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Junipers

Small patches appear and turn brown on junipers.

Two fungal diseases attack junipers. Kabatina tip blight is usually restricted to shoot tips and infects through wounds caused by insects or mechanical damage. Phomopsis tip blight is caused by spores produced during wet, cool periods in spring or fall; the spores are spread by splashing rain or overhead irrigation. Similar symptoms result from damage from two different insects. All affected areas should be pruned out; avoid overhead watering.

Decline can be caused by a combination of factors: improper pH/magnesium deficiency, Phytophthora root rot, tip blights, excess shade - Junipers require full sun; they will decline in shade, spider mites, poor drainage -Junipers do not do well in heavy clay soil. 1) Ends are turning black and dying. Small patches appear and turn brown on junipers. Juniper: Could be a nutritional problem. Improper pH can lead to deficiencies of certain nutrients, causing chlorosis. 2) Some shoots show reddening on tips. Juniper needles naturally turn a reddish brown color over the winter. 3) Dropping needles and dying from inside out. The plant could be root bound, when roots have not grown out of the original root ball and established themselves in surrounding soil, resulting in poor water uptake and a gradual decline of the plant. Scrape roots loose on the outside of the root ball before planting to encourage root growth and water adequately after transplanting, especially during a drought season. 4) Phytophthora root rot: This disease is favored by wet soil conditions. If drainage is a problem, try to correct before replanting. If over watering is the problem, cut back on watering remaining plants. Planting on raised beds can help with drainage. Plants with extensive browning usually have severe root rot and can not be saved.

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