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Damping-off

Several soilborne

66 host plants

Last updated

Data Coverage 3 of 6 dimensions
Causal Agent
Host Plants
Symptoms
Management
GDD Threshold
Regional Notes

In nurseries and seed beds, damping-off kills seedlings either before they emerge from soil (preemergence damping-off) or shortly after sprouting when they suddenly collapse and wilt. Seedlings appear healthy when they're underground, but wilt dramatically once they break the soil surface. The problem is most severe in cool, wet conditions when soil moisture stays high, and it can devastate entire seed trays or nursery beds, especially in Douglas-fir and other conifer seedlings grown in cool, maritime nurseries.

Damping-off is caused by multiple soilborne fungi, most commonly Fusarium and Pythium, and it thrives in wet, poorly drained soil. Prevention depends on controlling soil conditions and pathogen contamination from the start: use properly conditioned seeds, avoid waterlogged soil, and rotate planting beds with nonsusceptible crops like small grains to reduce fungal populations. Never reuse containers without disinfecting them; if you reuse styroblocks, sanitize them with heat or approved biocides. These practices interrupt the disease cycle and protect your seedlings through their most vulnerable stage.

Quick Reference

Causal Agent
Several soilborne
Host Plants
66

Management

Cultural Controls

  • Avoid poorly drained soil.
  • Use seeds that are properly conditioned.
  • Rotate planting beds with nonsusceptible hosts such as small grains to reduce fungal inoculum levels.
  • Avoid legume cover crops.
  • Keeping beds weed free and fallow with periodic tilling during inter-rotational seasons is even better.
  • Designate separate isolation beds for growing nursery stock that arrives from other nurseries.

Host Plants (66)

Ceratonia siliqua Carob St. John's Bread Locust, Bean Delphinium Larkspur Dermatophyllum secundiflorum Mescal Bean Texas Mountain Laurel, Frijolito Magnolia acuminata Cucumber Magnolia, Cucumbertree Magnolia, Mountain Magnolia Picea abies Norway Spruce Picea abies var. pendula Weeping Norway Spruce, Pendulous Norway Spruce Picea asperata Dragon Spruce Picea breweriana Brewer Spruce, Brewer's Weeping Spruce Picea engelmannii Engelmann Spruce Picea gemmata Szechwan Spruce Picea glauca White Spruce, Canadian Spruce, Skunk Spruce Picea koyamae Koyama's Spruce, Yatsugatake-tohi [Japanese] Picea mariana Black Spruce, Bog Spruce, Swamp Spruce Picea omorika Serbian Spruce Picea orientalis Caucasian Spruce, Oriental Spruce Picea pungens Colorado Spruce Picea pungens var. glauca Colorado Blue Spruce Picea rubens Red Spruce Picea sitchensis Sitka Spruce Picea wilsonii Wilson's Spruce Pinus albicaulis Whitebark Pine, Scrub Pine, White Pine Pinus aristata Bristlecone Pine, Rocky Mountain Bristlecone Interior Bristlecone Pinus attenuata Knobcone Pine Pinus banksiana Jack Pine, Scrub Pine, Banksian Pine, Hudson Bay Pine Pinus bungeana Lacebark Pine, Whitebark Pine, Baipi Song Pinus canariensis Canary Island Pine Pinus cembra Swiss Stone Pine Pinus contorta Lodgepole Pine Pinus contorta var. contorta Shore Pine Pinus contorta var. latifolia Rocky Mountain Lodgepole Pine Pinus coulteri Coulter Pine, Bigcone Pine Pinus densiflora Japanese Red Pine Pinus edulis Pinyon Pine, Piñón Pine, Two-needle Pinyon Colorado Pinyon Pinus elliottii Slash Pine, Swamp Pine Pinus flexilis Limber Pine, Rocky Mountain White Pine Pinus halepensis Aleppo Pine, Jerusalem Pine Pinus heldreichii Bosnian Pine, Snakeskin Pine Pinus jeffreyi Jeffrey Pine, Western Yellow Pine, Bull Pine Pinus kwangtungensis Kwangtung Pine, Guangdong Pine Pinus lambertiana Sugar Pine Pinus leucodermis Bosnian Pine Pinus monophylla Singleleaf Pinon Pine, One-leaved Pine Pinus monticola Western White Pine Pinus mugo Mugo Pine Pinus mugo var. pumilio Mugo pine, Dwarf Mugo pine Pinus nigra Austrian Pine Pinus parviflora Japanese White Pine Pinus parvifola Pinus parvifola Pinus pinaster Maritime Pine, Cluster Pine, Turpentine Pine Pinus pinea Italian Stone Pine, Umbrella Pine Pinus ponderosa Ponderosa Pine, Western Yellow Pine Pinus pumila Japanese Stone Pine, Dwarf Siberian Pine Pinus radiata Monterey Pine Pinus resinosa Red Pine Pinus sabiniana Gray Pine, Foothill Pine Pinus strobiformis Southwestern White Pine, Mexican White Pine, Chihuahua White Pine Pinus strobus Eastern White Pine Pinus sylvestris Scots Pine, Scotch Pine Pinus thunbergii Japanese Black Pine Pinus virginiana Virginia Pine, Scrub Pine, Jersey Pine Pinus wallichiana Himalayan Pine, Bhutan Pine Pinus yunnanensis Yunnan Pine Sophora secundiflora Mescal Bean Texas Mountain Laurel, Frijolito Trifolium tridentatum Tomcat Clover Verbena Purple Vervain Viola Hookedspur Violet