Many species of fungi form a mycelium, an indeterminate system of branching tubes. Fungal mycelia are essential components of many ecosystems allowing for the recycling and redistribution of nutrients and minerals over far greater distances and with greater efficiency than would be possible in their absence. These networks generally grow and function in a heterogeneous environment and hence any true understanding of their form and function must consider such heterogeneity. We discuss a model derived to study the interaction of the mycelium with a patchy nutrient environment. Comparisons are made with experimental results and conclusions drawn as to global nature of the mycelium's response.