Morchella populiphila is a species of morel fungus (family Morchellaceae) native to northwestern North America.

The morel used to be referred to as Morchella semilibera in western North American field guides until molecular analysis established that to be a strictly European species.

Its fruit bodies grow up to 15 cm (6 in) tall with a ridged and pitted conical cap that attaches about halfway down the stipe.

The fungus used to be referred to as Morchella semilibera (the "half-free morel") in western North American field guides until molecular analysis established that to be a strictly European species.

[4] The fragile, whitish to watery tan flesh is 1–2 mm thick in the hollow cap, and sometimes forms chambers or layers near the base.

[3] Although Morchella populiphila is an edible species, it is not as highly valued as other morels because of its fragile nature and its inferior flavor.

[4] The other North American half-free morel, Morchella punctipes, is very similar in appearance to M. populiphila, and they cannot be reliably distinguished on morphology alone.

[5] The widespread European species Morchella semilibera is morphologically indistinguishable from M. populiphila, in both macroscopic and microscopic characteristics.

[3] Like many morel species,[6] the ecological mode of Morchella populiphila is not known with certainty, but it is suspected of being both saprobic (obtaining its nourishment from nonliving or decaying organic matter) and mycorrhizal (symbiotic with trees) at different stages in its life cycle.