Mycologists do not significantly study physiology, because filamentous fungi cannot be studied in liquid media the way bacteria and yeasts can. And mycologists are cut off from microbial physiology being located in botany departments instead of microbiology departments.

The way to study the nutrition of filamentous fungi is to measure rate of growth over an agar surface. Culture tube slants can be used allowing the large number of tests that is needed. By measuring rate of mycelial extension, at least when there is a clear growing front, as with the morel mushroom, the sensitivity will distinguish between different brands of glucose.

This method is very informative, because the mycelium is growing over the surface of new media, which creates uniformity without interference from byproducts of growth. Colored pH indicators can be added to the medium to study changes in pH as the mycelium ages. There are zones formed, as the age increases farther back on the slants. This information tells the adequacy of buffers and excretion of byproducts or differential absorption of nutrients.