Flower:

Male and female flowers are on separate plants (dioecious) in spike-like clusters (catkins) at the tips of very short branchlets or from buds along 1 year old branches, emerging with or just before the leaves. Male catkins are ½ to about 1 inch long, the flowers densely to somewhat loosely packed, each flower with 2 yellow-tipped stamens.

Female catkins are ½ to about 1 inch long, the flowers somewhat loosely arranged on the spike, pear to horn-shaped, short-hairy, and on slender stalks 1.5 to 4 mm long. At the base of each male and female flower stalk is a dark brown, rose or bi-color scale-like bract covered in straight white hairs.

Leaves and stems:

Leaves are alternate, 1½ to 4 inches long, to ¾ inch wide, 4 to 9 times as long as wide, narrowly elliptic to lance-elliptic, widest below, at or just above the middle, tapering to a pointed tip, mostly wedge-shaped at the base, finely toothed around the edges, occasionally toothless or nearly so. The upper surface is dark green, the lower surface paler blue-green to gray-green. Leaf-like appendages at the base of the leaf stalk (stipules) are mostly absent.

New leaves are sparsely to moderately covered in silky white hairs on one or both surfaces, often mixed with some rusty-colored hairs, becoming sparsely hairy to hairless with age. Veins are not prominent on the underside. New branchlets are minutely hairy and green to yellowish, turning hairless and red-brown to dark red to purplish the second year. Bud scales are large and blackish.

Stems are slender, erect, numerous, have smooth to slightly rough greenish to gray bark and can reach 1½ inches diameter.

Fruit:

The spike elongates some as fruit matures, the fruit becoming more loosely arranged than the flowers.

Fruit is a capsule 5 to 9 mm long, yellowish when mature, short-hairy, pear-shaped, inflated at the base with a long straight to slightly curved beak. The capsule splits into two halves when mature, releasing the cottony seed.

Notes:

There are over 20 species of Willows in Minnesota; Meadow Willow is one of the most common species in the state, a medium to large, multi-stemmed shrub, found in a variety of moist to wet places including lake and pond margins, swamps, wet meadows and wet ditches, often with other Willow species but frequently the dominant species. It is recognized by the numerous slender stems often less than 1 inch diameter; typically at least some dark red branches; lack of stipules; narrowly lance to elliptic toothed leaves that are dark green on the upper surface and paler blue-green to gray-green on the lower, hairless to sparsely hairy; new leaves commonly with some rusty-colored hairs; hairy capsules 5 to 9 mm long on stalks up to 4 mm long; male flowers have 2 stamens. Both male and female flowers are subtended by a tiny, dark brown, rosy or bi-color bract covered in straight white hairs. It spreads only by seed, unlike many other Willow species.

The leaf shape is similar to several other willows, such as Black Willow (Salix nigra), Missouri River Willow (Salix eriocephala), and Pussy Willow (Salix discolor), all of which usually have at least some persistent stipules, which Meadow Willow lacks. Black Willow leaves are also about the same color green on both sides and fruit is hairless; Missouri River Willow has large, prominent stipules, usually proportionately broader leaves, and hairless fruit; Pussy Willow has thicker lower stems that are frequently branched near the base. Fruiting catkins of Meadow Willow tend to be shorter and stouter than all of the above.

Salix petiolaris hybridizes with several other Minnesota Willows; the single recorded occurrence of Salix bebbiana x petiolaris was in 1915 at a Minneapolis park and the single Salix eriocephala x petiolaris was at Schaefer Prairie in McLeod County in 1972.