TABLE 2.1 Isolation distances required by USDA for producing foundation seed used for seed increase. Note that this is not a complete list of all crops

Crop Speciesa

Distance, ft

Maximal Proportion Contaiminated, %b

No isolation required:

Barley

0

0.05

Bean, field and garden

0

0.05

Broad bean

0

0.05

Cotton

0

0.03

Flax

0

0.05

Millet, selfed

0

0.05

Mung bean

0

0.10

Oat

0

0.02

Pea, field

0

0.50

Peanut

0

0.10

Soybean

0

0.10

Triticale

0

0.05

Wheat

0

0.50

Isolation Required:

Alfalfa

600

0.10

Buckwheat

660

0.05

Clover, < 2 ha

600

0.10

Clover, > 2 ha

900

0.10

Corn

660

0.10

Crown vetch, < 2 ha

200

0.10

Crown vetch, > 2 ha

900

0.10

Grasses, cross-pollinated

900

0.10

Grasses, selfed

60

0.10

Lespedeza

10

0.10

Millet, cross-pollinated

1,320

0.005

Mustard

1,320

0.05

Okra

1,320

0.0

Onion

5,280

0.0

Pepper

200

0.0

Rape, cross-pollinated

1,320

0.05

Rape, selfed

660

0.05

Rice

10

0.05

Rye

660

0.05

Safflower

1,320

0.01

Sorghum

900

0.005

Sunflower

2,640

0.02

Tobacco

150

0.01

Tomato

200

0.0

Trefoil, birdsfoot

600

0.10

Vetch

10

0.10

Vetch, milk

600

0.05

Watermelon

2,640

0.0

aCommon name.

bMaximal percentage produced from pollen outside plot.

Source: From regulations listed in table 5 of USDA (1994a).



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