Summary:
Clade Deliciosi. Characteristic features of the Lactarius deliciosus group are the orange color when young, orange milk (that may turn reddish on exposure to air), and green staining, usually after an intervening dark red staining stage. The caps tend to be zoned and the stems are sometimes scrobiculate. Taste is mild, slightly bitter, or slightly peppery. |There are at least four taxa occurring in North America that have gone under the name Lactarius deliciosus in North America, ''deliciosus'' not being the correct name for any of them, but new names have not been proposed yet (Nuytinck(1), 2006, Nuytinck(3), 2007, Nuytinck(4), 2014). We also have no confirmation from the Pacific Northwest that Lactarius deterrimus occurs. |We are including in this group (by appearance) two similar but not as closely related species in the Pacific Northwest that were described this century: the common Lactarius aestivus with little green staining (Nuytinck(4), 2014) q.v., and Lactarius aurantiosordidus (Nuytinck(1), 2006) q.v. (which they say bears a resemblance to L. deliciosus var. olivaceosordidus but does not group with the collections of what Hesler(4) was describing as L. deliciosus from North America). They also describe Lactarius deliciosus var. olivaceosordidus without synonymizing it. (Nuytinck(1), 2006). In addition, Nuytinck(1) mention two collections from Washington identified as Lactarius deliciosus var. olivaceosordidus, one of which groups with other collections identified as Lactarius ''deliciosus'' or one of its varieties and the other does not (they do not mention whether the latter is close to Lactarius aurantiosordidus). Their conclusion is that Lactarius deliciosus var. olivaceosordidus as currently identified in North America is polyphyletic. |By whatever name(s), Lactarius deliciosus group represents common mushrooms in the Pacific Northwest. The next four paragraphs are historical information and should be skipped by most people. |We will retain some varietal names for convenience. A macroscopic key to varieties is given in Leuthy(1) as follows. If milk is muddy carrot or reddish carrot at first and cap tissue yellowish this is var. olivaceosordidus. If milk is muddy carrot or reddish carrot at first but cap tissue is reddish carrot under surface drying dull red in 15 minutes, this is var. piceus. If milk is bright orange at first, then becomes deep purplish red before green, and cap becomes areolate [cracked like dried mud], this is var. areolatus. If milk is bright orange at first, then stains tissues purple (vinaceous) before green, and the cap does not become areolate, this is var. deterrimus. If milk is bright orange at first, but does not change to red or purple shade within 15-30 minutes (before green), this would be var. deliciosus. |Hesler(4) gives the following analogous key to varieties, using microscopic characters. If the macrocystidia type of pleurocystidia are present, var. piceus stains red when cut and has spores 7.5-9 x 6.5-8 microns and var. olivaceosordidus stains yellowish when cut and has spores 8.5-10.5 x 6.5-8 microns. If on the other hand macrocystidia are absent, var. areolatus stains slowly wine-red when cut, spores are 8.5-11(12) x 6-8.5 microns, and cap often becomes areolate, var. deterrimus stains slowly wine-red when cut but spores are 7.5-9 x 6-7 microns and cap does not become areolate, and var. deliciosus does not stain dark red (it has spores 7-9 x 6-7 microns). |Some authors (e.g. Bessette(2)) give Lactarius deterrimus Groeger as the common North American species "often incorrectly called L. deliciosus, which is a similar European species" (Latin name italicized). This is the Lactarius deterrimus that Hesler(4) synonymized to form Lactarius deliciosus var. deterrimus above. See the Lactarius deterrimus entry for further details. Please see Matchmaker for addtional details.

Cap:
5-16cm across, broadly convex or with a depressed center and inrolled margin when young, "becoming depressed or shallowly funnel-shaped"; "color variable: dull orange to carrot-orange or orange-brown, sometimes blotched with or entirely green, fading in age or dry weather to brownish, gray, dull greenish-gray, or even yellowish", often zoned; surface viscid when moist but soon dry, smooth, (Arora), may be up to 35cm across, (Ammirati)

Flesh:
thick, brittle; orange to yellowish or greenish, (Arora), MILK very scanty; bright carrot-orange (but in some forms slowly turning dark red when exposed) slowly staining wounded or aged tissue greenish (within 5 hours), (Arora)

Gills:
adnate to decurrent, close; "typically bright to dull orange, but varying to yellowish or orange-buff, greenish where wounded", (Arora)

Stem:
2-7cm x 1-2.5cm, equal or narrowed at base, rigid, hollow when old; colored like cap or paler; soon dry, sometimes scrobiculate, frequently maggot-riddled, (Arora)

Veil:
[none]

Odor:
slightly fruity (Phillips), mild to slightly fruity or (var. areolatus) Morchella-like (Leuthy), fruity, peach-like, (Lincoff(2))

Taste:
mild or slightly bitter (Arora), mild or slightly bitter or slightly peppery (Leuthy), mild to slightly soapy (Kibby)

Microscopic spores:
spores 7-11 x 6-8 microns, broadly elliptic to nearly round, with amyloid ridges (Arora), var. areolatus spores (7)8.5-11(12) x 6-8.5 microns, broadly elliptic, ornamentation in form of +/- heavily amyloid system "of bands often widely spaced to form a partial to broken reticulum", prominences +/- 0.3-0.5 microns high, basidia 4-spored, 42-54 x 9-12 microns, pleurocystidia: macrocystidia none, occasionally "cheilocystidia" near edge, pseudocystidia "numerous, filamentous, crooked", cheilocystidia abundant, 25-44 x 2.5-4(6) microns, narrowly fusoid-ventricose to aciculate; var. olivaceosordidus: spores 8.5-10.5 x 6.5-8 microns, nearly round to broadly elliptic, ornamentation +/- heavy, "of bands and crests forming a partial reticulum, the meshes often wide, some granules and warts present also", prominences +/- 0.5 microns high, basidia 4-spored, pleurocystidia: macrocystidia scattered, embedded, 42-63 x 3-5 microns, "aciculate to filamentose (almost like pseudocystidia which are also present)", cheilocystidia similar to pleurocystidia; var. piceus: spores 7.5-9 x 6-7.5 microns, often near oblong, "ornamentation in the form of a wide-meshed broken reticulum or the reticulum scarcely evident", with prominences 0.2-0.4 microns high, basidia 4-spored, 44-57 x 8-10 microns, pleurocystidia: macrocystidia more numerous near edges, 40-70 x 3-5 microns, fusoid or somewhat filamentous, pseudocystidia filamentous, cheilocystidia 33-40 microns long, similar to pleurocystidia; var. deliciosus: spores 7-9 x 6-7 microns, "with minute warts and bands forming a partial reticulum"; basidia 4-spored, 36-45 x 8-9 microns, cystidia sparse, aciculate, 40-50 x 4-6 microns, according to section in key macrocystidia absent or limited to region of gill edge; var. deterrimus: spores 7.5-9 x 6-7 microns, broadly elliptic, "ornamentation with a partial or broken reticulum with additional isolated warts and ridges", prominences 0.5-0.8 microns high, basidia 4-spored, 45-50 x 9-11 microns, pleurocystidia: "macrocystidia absent or a few similar to cheilocystidia near the edge", 35-50(65) x 3-6 microns, aciculate, pseudocystidia scattered, filamentous, cheilocystidia scattered, 30-40 x 3-6 microns, aciculate, (Hesler)

Spore deposit:
creamy yellowish buff (Arora)

Notes:
According to Hesler(4), var. areolatus is thought to be the common western variety during some seasons at least (material cited from OR, ID (including holotype), AK, CO, NM, WY, (Hesler(4)). Var. areolatus also reported from western AB by Kernaghan(1), and from CA by Methven(2)). Var. olivaceosordidus material was cited from OR, including the holotype, (Hesler(4)), and reported from CA (Methven(2)). Var. piceus was cited from WA, ID, CA, (Hesler(4)). Lactarius "deliciosus" has also been listed from BC (Redhead(5)).

EDIBILITY

yes, but grainy texture, (Arora), according to Sept(1) turns urine red