Summary:
Features include 1) smooth, viscid to glutinous cap that is red-brown to yellow-brown, 2) unchanging flesh and pores that are white to pale yellow, 3) conspicuous whitish sheathing annulus which is often viscid or with a lavender band or layer externally, 4) prominent glandular dots during all stages on a white to pale yellow upper stem, and 5) growth under conifers. "Suillus luteus is the most widespread species in the world, occurring in the Northern and Southern Hemisphere. It is native to Europe, where it associates with P. sylvestris and P. nigra, but it has also been introduced into North and South America, Asia, and Australasia with P. sylvestris"; it has been recorded with several other pine species internationally, (Nguyen).

Chemical Reactions:
cap cuticle dull dark gray with application of KOH, grayish olive with FeSO4; flesh pinkish then pale blue-gray with KOH, grayish blue to olive with application of FeSO4, (Bessette)

Odor:
not distinctive (Bessette, Smith(34))

Taste:
not distinctive (Bessette), pleasant (Smith(34))

Microscopic:
"spores 7-9 x 2.5-3 microns, nearly oblong, smooth, pale brown", (Bessette), spores 7-9 x 2.5-3 microns, smooth, with pronounced colorless sheath, more or less oblong, inamyloid, nearly colorless in KOH; basidia 4-spored, 14-18 x 4-5 microns, yellowish in KOH; pleurocystidia "in scattered to rare bundles surrounded by bister debris", "when isolated 20-35 X 5-7 microns and narrowly clavate, content usually bister as revived in KOH", cheilocystidia "similar, but tube edges often a mass of bister incrustation obscuring the cystidia"; cap cuticle of gelatinous filaments 2-4 microns wide, forming a tangled trichodermium, colorless in KOH and pale yellowish in Melzer''s reagent; stem with numerous fascicles of caulocystidia, the clusters bister in KOH; clamp connections not seen, (Smith(34)), spores 7-10 x 3-3.5 microns, (Lincoff(1))

Spore Deposit:
brown, (Bessette), ''"sayal brown" to "clay color" dull cinnamon when moisture has escaped'' (Ridgway colors), (Smith(34)), brown to dull cinnamon (Arora)

Notes:
Suillus luteus is widely distributed through North America (Bessette). The exact RANGE is uncertain because the name has been applied to almost any Suillus with an annulus, (Smith(34)), and Smith(36) noted in 1965 "In the light of our more restricted concept of S. luteus its presence in the Pacific Northwest needs further verification." It was found in MI (Smith(34) in 1964), and has been reported from BC (in Redhead), WA, OR, (both vouchered at University of Washington and at Oregon State University), ID (K. Chadwick, pers. comm.; vouchered at Oregon State University), CA (Thiers), NS (Grund), and also Europe and Asia (Breitenbach).

EDIBILITY

yes (Bessette), some people are apparently "allergic" to it, (Arora), may cause transient diarrhea if slime not removed, (Lincoff(2)), good after removing cuticle and drying, although some experience diarrhea, (Lincoff(1))