While most species display a preference towards either broadleaf or coniferous hosts, some are more strictly associated with certain genera or species of plant hosts. A well-studied example is that of alders, which have several specialized "Lactarius" symbionts (e.g. "L. alpinus", "L. brunneohepaticus", "L. lilacinus"), some of which even evolved specificity to one of the "Alnus" subgenera. Other examples of specialized associations of "Lactarius" are with "Cistus" shrubs ("L. cistophilus" and "L. tesquorum"), beech (e.g. "L. blennius"), birches (e.g. "L. pubescens"), hazel (e.g. "L. pyrogalus"), oak (e.g. "L. quietus"), pines (e.g. "L. deliciosus"), or fir (e.g. "L. deterrimus"). For most tropical species, host plant range is poorly known, but species in tropical Africa seem to be rather generalist.