Economic thresholds generally do not exist for plant pathogens and nematodes in Idaho field and row crops.  The following table instead lists pesticide application timing recommendations for disease and nematode management.

Barley

Pathogen		Pesticide	Timing
	Barley yellow dwarf virus (BYDV)	Granular systemic insecticides in-furrow	Apply granular systemic insecticides to reduce numbers of aphids that transmit BYDV.
	Powdery mildew (Erysiphe graminis f. sp. hordei)	Tilt fungicide at 4 oz/A in not less than 15 gal/A water (ground) or 5 gal/A water (air).	Apply Tilt fungicide at flag leaf emergence (Feekes 8) but not after this stage.
	Scald (Rhynchosporium secalis)	Tilt fungicide at 4 oz/A in not less than 15 gal/A water (ground) or 5 gal/A water (air).	Apply Tilt fungicide at flag leaf emergence (Feekes 8) but not after this stage.
	Stem rust (Puccinia graminis)	Tilt fungicide at 4 oz/A in not less than 15 gal/A water (ground) or 5 gal/A water (air).	Apply Tilt fungicide at flag leaf emergence (Feekes 8) but not after this stage.
	Stripe rust (Puccinia striiformis f. sp. hordei)	Tilt fungicide at 4 oz/A in not less than 15 gal/A water (ground) or 5 gal/A water (air).	Apply Tilt fungicide at flag leaf emergence (Feekes 8) but not after this stage.

Wheat

Pathogen		Pesticide	Timing
	Eyespot - Strawbreaker foot rot (Pseudocercosporella herpotrichoides)	Protectice or curative fungicide	Apply protective or curative fungicides at tillering but before elongations if field scouting shows that  10%  of stems sampled are infected.
	Leaf rust (Puccinia triticina)	Quadris Flowable fungicide at 6.2 to 10.8 fl oz/A	Application of Quadris Flowable fungicide may be made immediately after jointing (Feekes 6) upt to late head emergence (Feekes 10.5).
		Tilt fungicide at 4 oz/A in not less than 15 gal/A water (ground) or 5 gal/A water (air).	Tilt fungicide at 4 oz/A in not less than 15 gal/A water (ground) or 5 gal/A water (air).
	Powdery mildew (Erysiphe graminis f. sp. tritici)	Quadris Flowable fungicide at 7.7 to 10.8 fl oz/A	Flowable fungicide may be made immediately after jointing (Feekes 6) upt to late head emergence (Feekes 10.5)
		Tilt fungicide at 4 oz/A in not less than 15 gal/A water (ground) or 5 gal/A water (air).	Tilt fungicide at 4 oz/A in not less than 15 gal/A water (ground) or 5 gal/A water (air).
	Seporia leaf blotch & glume blotch (Septoria tritici & S. nodorum)	Quadris Flowable fungicide at 6.2 to 10.8 fl oz/A	Application of Quadris Flowable fungicide may be made immediately after jointing (Feekes 6) upt to late head emergence (Feekes 10.5).
		Tilt fungicide at 4 oz/A in not less than 15 gal/A water (ground) or 5 gal/A water (air).	Tilt fungicide at 4 oz/A in not less than 15 gal/A water (ground) or 5 gal/A water (air).
	Stem rust (Puccinia graminis)	Quadris Flowable fungicide at 6.2 to 10.8 fl oz/A	Application of Quadris Flowable fungicide may be made immediately after jointing (Feekes 6) upt to late head emergence (Feekes 10.5).
		Tilt fungicide at 4 oz/A in not less than 15 gal/A water (ground) or 5 gal/A water (air).	Tilt fungicide at 4 oz/A in not less than 15 gal/A water (ground) or 5 gal/A water (air).
	Stripe rust (Puccinia striiformis)	Quadris Flowable fungicide at 6.2 to 10.8 fl oz/A	Application of Quadris Flowable fungicide may be made immediately after jointing (Feekes 6) upt to late head emergence (Feekes 10.5).
		Tilt fungicide at 4 oz/A in not less than 15 gal/A water (ground) or 5 gal/A water (air).	Tilt fungicide at 4 oz/A in not less than 15 gal/A water (ground) or 5 gal/A water (air).

    References:  Pacific Northwest Disease Control Handbook, 2000.

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