Nursery trade got Congress to create a plant patent for asexual propagation

A plant breeder could spend a decade crossing and selecting to arrive at a new rose, apple or peach, and then had nothing to sell but the plants themselves. Anyone who bought a single specimen could graft it indefinitely and sell the offspring in competition with the breeder, at a price that never had to carry the cost of the breeding. Growers, as the House archive records, 'had long complained that without legal safeguards their products, which often took years to perfect, were replicated and sold by others.'

The patent system was no help, because it was built around a manufacture — something a person made — and a plant was treated as a product of nature that a breeder had merely found or coaxed. The gap was stated most memorably by Representative Fred Purnell of Indiana, an eight-term member of the Agriculture Committee: 'Why should a man who invents a mouse trap or a jazz song have protection and enjoy the privileges that the patent system gives him, and a man like Luther Burbank, who spent his life developing new plants, get nothing?'

Rather than litigate, the nursery trade had Congress create a parallel right for asexual propagation only, excluding seeds and grains to avoid farm opposition.

Existing patent law covered only manufactures, not plants, so litigation to stretch the definition was slow and uncertain.

A parallel right could be drafted to match the actual asset: asexual propagation, which is how nurseries reproduce varieties.

Excluding seeds and staple crops removed the farm lobby's incentive to block the bill, making passage achievable.

The narrow scope meant the new right threatened few powerful interests, so it passed quickly and established a precedent.

When your creation doesn't fit an existing legal category, consider creating a new one tailored to your asset, and keep it narrow to avoid opposition.

The House passed the Plant Patent Act on 13 May 1930; the first plant patent went to a climbing rose the next year. The Act established the principle that living plant varieties could be private property, and the boundary it drew was widened by later law rather than overturned: the Plant Variety Protection Act of 1970 reached seed-propagated crops, and plant breeders' rights on the same model spread internationally through the UPOV convention. The staple-crop exclusion the 1930 Act needed to survive is exactly the territory the fight later moved to.