These are produced by grafting different parents, different cultivars or different species (which may belong to different genera). The tissues may be partially fused together following grafting to form a single growing organism that preserves both types of tissue in a single shoot. Just as the constituent species are likely to differ in a wide range of features, so the behavior of their chimera is like to be highly variable. In horticulture, a graft-chimaera may arise in grafting at the point of contact between rootstock and stem and will have properties intermediate between those of its “parents”. A graft-chimaera is not a true hybrid but a mixture of cells, each with the genotype of one of its “parents”: it is a chimaera. Propagation is by cloning only. In practice graft-chimaeras are not noted for their stability and may easily revert to one of the “parents”. Chimeras can also be produced in animals.