This genus of the Boletaceae is the most common and softest fleshed member of the family. These mushrooms are mycorrhizal with pine trees, and often dominate the mushrooms found in this habitat. They can be quite plentiful, and there are no toxic members of the genus. Maggots will often ruin a harvest, however, as they seem to like them much more than people do.
This is one of the commonly encountered Suillus mushrooms. This appears to be an older member of S. luteus group, depending on the surrounding conifer, which will vary in different parts of the US or Canada.
Suillus like this S. grevillei are often found fruiting next to Gomphidius glutinosus or other Gomphidius. It is believed that the Gomphidius are parasitic on the Suillus, which are arguably the most common mushroom in our northern conifer forests.