Leaf Blight

Fungal agents (multiple)

46 host plants

Last updated

Data Maturity Baseline

This profile contains verified disease data from extension databases. Regional field notes and expert review are in progress.

Water-soaked lesions expand into brown spots with distinctly darker margins, causing significant premature defoliation that weakens the plant substantially. Remove affected foliage immediately when symptoms appear, improve soil drainage around roots, and space plants for air movement. Rake fallen leaves regularly throughout the season. Avoid overhead watering which keeps foliage wet and spreads fungal spores.

Propagate from disease-free stock plants. Use seed from British Columbia coastal, low-elevation populations.

Quick Reference

Causal Agent
Fungal agents (multiple)
Host Plants
46

Management

Cultural Controls

  • Until more is known about fungal leaf blight on madrone, good sanitation practices should be used when practical.
  • Clean up and dispose of fallen blighted leaves around valuable landscape trees.
  • Avoid stressing madrones with poor planting location or improper culture.
  • They prefer native soils with excellent drainage, grow best in full or partial sun, and can tolerate poor soils.
  • Good air circulation is important since fungal diseases are more severe in crowded, humid conditions.
  • Do not irrigate established trees, as they are adapted to summer drought.

Host Plants (46)

Arbutus menziesii Pacific Madrone Arbutus unedo Strawberry Tree, Killarney Strawberry Tree, Madroño Athrotaxis laxifolia Tasmanian Pencil Pine, Summit Cedar Callitropsis nootkatensis Alaska Cedar, Nootka Cypress, Nootka Falsecypress, Yellow Cedar Calocedrus decurrens Incense Cedar Cedrus atlantica Atlas Cedar Cedrus brevifolia Cyprus Cedar Cedrus deodara Deodar Cedar, Himalayan Cedar Cedrus libani Cedar, of Lebanon Cedrus libani subsp. brevifolia Cypress Cedar, Cyprian Cedar Chamaecyparis lawsoniana Port Orford Cedar Chamaecyparis thyoides White Cedar, Atlantic Whitecedar, Whitecedar Falsecypress Cryptomeria japonica Japanese Cedar Juniperus californica California Juniper, California White Cedar, Desert White Cedar Juniperus cedrus Canary Island Juniper Juniperus chinensis Chinese Juniper Juniperus communis Common Juniper Juniperus conferta Juniperus conferta Juniperus deppeana Alligator Juniper, Checkered-bark Juniper Juniperus formosana Formosan Juniper Juniperus grey Juniperus grey Juniperus horizontalis Creeping Juniper Juniperus monosperma Oneseed Juniper Juniperus occidentalis Western Juniper Juniperus osteosperma Utah Juniper Juniperus pingii Ping Juniper Juniperus procumbens Japanese Garden Juniper, Bonin Island Juniper, Ibuki Juniper Juniperus rigida Temple Juniper, Needle Juniper Juniperus rigida subsp. conferta Shore Juniper Juniperus sabina Savin Juniper Juniperus scopulorum Rocky Mountain Juniper Juniperus squamata Singleseed Juniper, Flaky Juniper, gao shan bai Juniperus virginiana Eastern Redcedar Pencil Cedar Microbiota decussata Russian Arborvitae, Siberian Cypress Morella californica Pacific Waxmyrtle California Waxmyrtle California Bayberry Morella pensylvanica Northern Bayberry Candleberry Morella rubra Red Bayberry Chinese Bayberry Japanese Bayberry Platycladus orientalis Chinese Arborvitae, Oriental Arborvitae Taiwania cryptomerioides Formosan Redwood Taiwan Cedar Taiwania, Coffin Tree Tamarix parviflora Small-flowered Tamarix, Salt Cedar Thuja occidentalis Eastern Arborvitae, American Arborvitae Eastern White-cedar Thuja orientalis Chinese Arborvitae, Oriental Arborvitae Thuja plicata Western Redcedar Thujopsis dolabrata Elkhorn Cedar, Deerhorn Cedar, Hiba Arborvitae, False Arborvitae Widdringtonia nodiflora Berg Cypress Mountain Cypress, Mountain Cedar Widdringtonia schwarzii Willowmore Cedar