The species produces brown mushrooms with caps of varying shapes up to 40 millimetres (1.6 in) across, and tall, thin stems up to 62 mm (2.4 in) long.

Inocybe saliceticola was first described in 2009 by Jukka Vauras and Katri Kokkonen in the journal Karstenia, based on around 20 specimens from Finland, the majority of which were collected by the authors.

[8] Species within Marginatae similar to I. saliceticola include I. obtusiuscula, I. dunensis, I. salicis-herbaceae, I. substellata, I. praetervisa, I. salicis and I. mixtilis.

[4] In one case, however, an atypical specimen was recovered with an almost completely smooth stem, free of striations or powder.

The mushrooms also feature "paracystidia", club-shaped cystidia-like structures on the gills lacking crystals, as well as "cauloparacystidia" on the stem.

[10] Of the species of Marginatae associated with willow, five (I. salicis-herbaceae, I. substellata, I. praetervisa, I. salicis and I. mixtilis) can be readily distinguished from I. saliceticola as their spores feature distinct, strongly protruding excrescences.

Of the other two listed by Vauras and Kokkonen, the spores of I. dunensis are distinctly larger and of a different shape to those of I. saliceticola, and the cystidia are shorter.

I. obtusiuscula also has larger spores of a different shape, and they are a darker colour, owing to their thick cell walls.

Phylogenetic analysis of the respective internal transcribed spacer sequences has confirmed that I. obtusiuscula and I. saliceticola are separate species.

[5] Inocybe alnea and I. ochracea, regarded by some as the same species, can also be distinguished from I. saliceticola by the presence of protruding nodules on the spores.

Macroscopically, I. rivularis, which could grow in similar habitats to that of I. saliceticola, produces larger mushrooms and has powder only towards the top of the stem.

They are typically near plants such as the tufted loosestrife (Lysimachia thyrsiflora), the creeping buttercup (Ranunculus repens), the common marsh-bedstraw (Galium palustre), the purple marshlocks (Comarum palustre) and the purple small-reed (Calamagrostis canescens), and share the habitat with other Inocybe, including I. acuta and I. lacera var. helobia.

[10] Inocybe saliceticola has been recorded in several locations around Finland, ranging from the hemiboreal zones in the east and the south of the country, to boreal areas in the north, and it has also been found in Sweden, close to the Klarälven.

[10] It is one of over 150 species of Inocybe found in the Nordic countries,[3] and fruit bodies can be encountered between late July and early October.