Quiet Jack

The cap ranges in shape from hemispheric to broadly convex, and has a diameter of 6 to 12 cm (2.4 to 4.7 in). The cap color is deep brown in mature specimens and lighter shades of brown in younger mushrooms. Young specimens have a sticky layer of gluten on the cap that dries out in maturity. The edge of the cap is rolled inwards in young specimens. The flesh of the cap is whitish and does not change color when bruised or cut. The tubes on the underside of the cap are light yellow to bright orange-yellow; the tube mouths are usually less than 1 mm wide. The stipe is usually between 2 and 4 cm (0.8 and 1.6 in) long, less frequently reaching up to 8 cm (3.1 in). It is either the same width throughout or slightly larger (bulbous) at the base. The color of the upper portion of the stipe is pale to light yellow, while the lower portion may be light brown or covered with streaks of glutinous material like that on the cap. The stipe surface is covered with fine glands that are initially slightly darker than the color of the stipe surface, but deepen to brown or nearly black after drying. …

Fruit bodies grow together in small groups on the ground in association with bishop pine (Pinus muricata). In a multigene phylogenetic study of Suillus, S. quiescens was also sampled in California in association with Monterey pine (Pinus radiata), in addition to bishop pine. The IUCN Red List assessment reports that it is ectomycorrhizal with two- and three-needle pines and also occurs with lodgepole pine (Pinus contorta) on the northern California and Oregon coast; based on environmental samples, the assessment considers it likely to occur with Ponderosa pine (P. ponderosa) and Jeffrey pine (P. jeffreyi) as well, while noting that more data are needed on the species' ecology. S. quiescens is the most common Suillus species on Santa Cruz Island, its type locality, and it has also been collected at Santa Rosa Island and Point Reyes National Seashore in California. Santa Cruz and Santa Rosa, two of the four islands that make up the northern Channel Islands, have a Mediterranean climate with cool, wet winters and warm, dry summers. Most species of Suillus do not have spores that survive in the soil for extended periods of time, but the spores of S. quiescens can tolerate the dry conditions and heat typical of California. Another study showed that viable S. quiescens spores were present in steam-pasteurized soil planted in Oregon fields. The original description suggested that S. …