Merriam's chipmunks are herbivorous. They eat acorns, and other seeds and nuts of conifers, manzanita, juniper, and various chaparral species. They search for, and gather, food on the ground, in shrubs, and on stumps, logs, and snags. They may cache food for later use.
Burrows also provide cover.
Nests are built in logs, stumps, snags, and in burrows. Heavy brush associated with oaks, rock outcrops, logs, stumps, snags, and litter required by Merriam's chipmunks. Merriam's chipmunks breed from mid-January through June, with peak activity in April. Gestation period about 30 days. Females produce 1 litter per yr.