(1) “Secretary” means the Secretary of Agriculture of the Commonwealth.

(2) “Grape grower” means a producer of grapes for profit.

(3) “Grape vineyard” means lands upon which grapevines are maintained and harvested for profit.

(4) “Proximity” means a radial distance of two miles from the site of damage.

(5) “Development” means natural and normal growth before harvest.

(6) “Affected area” means the area defined in petition. The affected area may be altered by description in the order of the secretary, if the secretary finds that such alteration should be made to effectuate the purposes of the petition.

(7) “Major source of agricultural income” means that the producers of grapes within the affected area obtain at least ten percent of their gross farm income as a group in any five year period from the production of grapes.

(8) “Herbicide” means any agent used to destroy or inhibit plant growth.