Conjecture on unions of intersecting strictly informative groves

Let two groves be strictly informative if each satisfies the strict informativeness criterion for determining supertrees. Let the groves be collections of taxon sets, with intersection and union taken as collections of taxon sets. Strictly informative grove union conjecture. The union of two intersecting strictly informative groves is a grove.

This is proposed as a weaker statement related to the earlier conjecture on groves. The paper gives a counterexample showing that the union of two intersecting strictly informative groves need not itself be strictly informative, even when it is a grove; the conjecture asserts only the weaker grove property.