cross-fertilize vs cross-fertilise

cross-fertilize and cross-fertilise both are verbs.

Word	Noun	Adjective	Verb	Adverb
cross-fertilize	No	No	Yes	No
cross-fertilise	No	No	Yes	No

As verbs, cross-fertilize and cross-fertilise are synonyms defined as:

cross-fertilize and cross-fertilise: cause to undergo cross-fertilization

As verbs, cross-fertilize and cross-fertilise are synonyms defined as:

cross-fertilize and cross-fertilise: undergo cross-fertilization; become fertile

cross-fertilize (verb)	cross-fertilise (verb)
cause to undergo cross-fertilization	cause to undergo cross-fertilization
undergo cross-fertilization; become fertile	undergo cross-fertilization; become fertile