General: Willow Family (Salicaceae). Prairie willow is a colonial shrub as tall as 3m (10 feet) (McGregor et al. 1986, Stephens 1973). The young branches are yellow beneath the gray pubescence. Leaves are alternate, simple, lance-shaped, 6-10 cm (2.4-3.9 in) long. Leaves are dark green and usually glabrous above and densely short-hairy beneath, with the golden yellow veins raised prominently on the lower surface. Plants bloom from April to May and fruit in early June. Catkins emerge before the leaves. The pistillate (female) catkins are sessile, 1-4 cm (0.4-1.6 in) long, and ovoid-conic. The small, hairy capsules are 4-6 mm (1/4 in) long. When ripe, they open to release tiny wind-born seeds with silky hairs at their base.

dwarf willow, willow

Salix humilis Marshall:
Canada (North America)
United States (North America)

Note: This information is based on publications available through Tropicos and may not represent the entire distribution. Tropicos does not categorize distributions as native or non-native.

Canada

Origin: Unknown/Undetermined

Regularity: Regularly occurring

Currently: Unknown/Undetermined

Confidence: Confident

United States

Origin: Unknown/Undetermined

Regularity: Regularly occurring

Currently: Unknown/Undetermined

Confidence: Confident

Prairie willow grows in upland sites in prairies and sparse woods, especially in sandy soil. It grows in midwestern prairies in Minnesota, Iowa, Missouri, North Dakota, South Dakota, Nebraska, Kansas and Oklahoma. For current distribution, please consult the Plant Profile page for this species on the PLANTS Web site.

Willows root freely from cuttings, and are easy to propagate. Willows are difficult to propagate in quantity by seed.

The NRCS, Plant Materials Center, Los Lunas, New Mexico, in cooperation with the U.S. Fish and Wildlife Service, developed a pole planting technique for establishing willow (Hoag 1993a). We reprint this procedure below. "Trial planting on well adapted sites indicate more that 80% survival of cottonwood and willow poles when dormant poles are cut and planted between November and February. It is essential to monitor the water tables at proposed planting sites for at least one year before planting. Poles planted where the water table fluctuates widely will have lower survival rates than those planted where water table is relatively stable. If groundwater monitoring shows the water level will drop more than 3 feet during the growing season (May-October), another site should be selected. Monitoring of observation wells for at least one calendar year before planting will allow better planting depth to ensure establishment."

Steps for Successful Pole Plantings

• Select collection sites as close to the area as possible to conserve genetic diversity. Try to match donor site and revegetation site in terms of soils, elevation, hydro-dynamics, permanent groundwater table, and soil salinity (which should be low).

• Select willow cuttings from a local, native stand in healthy condition. Prune no more than 2/3 of plants in an area. Willow cuttings for pole plantings should generally be at least 1/2 inch in diameter or larger. Select the longest, straightest poles available. Use only two to four-year old wood. The total length of the poles needed depends upon the water table depth.

• Measure water table fluctuations in the planting area for at least 1 year, preferably longer, to determine the lowest water table depth. Take a reading at least once a month, preferably more often during the driest months of the year.

• Cut poles while dormant. Remove all side branches except the top two or three.

• Prepare cuttings by trimming off the top to remove the terminal bud, allowing a majority of the energy in the stem to be sent to the lateral buds for root and shot development.

• Soak poles in water for at least 5 to 7 days before planting.

• Dig holes to the depth of the lowest anticipated water table. Sites where the water table will be within one foot of the ground surface during the growing season are better suited for willows than cottonwoods.

• The cuttings should extend several inches into the permanent water table to ensure adequate moisture for sprouting. At least 1/2 to 2/3's of the cutting should be below ground to prevent the cutting from being ripped out during high flows. Usually, at least 2 to 3 feet should be below ground. It should also be long enough to emerge above adjacent vegetation such that it will not be shaded out.

• Place the cuttings in the holes the same day they were removed from the soak treatment. Set the butt as close to the lowest annual water table elevation as possible.

• Electric hammer drills (Dewalt model DW530) fitted with one-inch diameter, 3-foot bits were used to plant thousands of willows in New Mexico. With one drill, two people installed 500 willow cuttings per day to a 3-foot depth. A power auger or a punch bar can also be used.

• Willow pole cuttings were generally planted on 10 to 20 foot centers in New Mexico. Areas with a shallow water table (4-6 feet) were generally planted with a higher number of pole cuttings to enhance overall survival. Often understory species were planted under the canopy of pre-existing overstory (cottonwoods, tree willows), since they are often observed occupying this niche.

• It is critical to ensure that the soil is packed around the cutting to prevent air pockets. "Mudding" (filling the hole with water and then adding soil to make mud slurry) can remove air pockets.

• When necessary, install tree guards around the poles to protect from beavers, other rodents, or rabbits. Willows tend to be fairly resistant to pruning from beavers, so tree guards may not be necessary.

• As buds begin to swell (usually in April or May), remove them from the lower two-thirds of the pole. This will reduce evapotranspiration water loss and stimulate root growth.

• Exclude the planting area from livestock grazing for at least two to three growing seasons.

Seed Collections

• Willow seeds must be collected as soon as the capsules mature (when they turn from green to yellow or tan).

• Plant seeds immediately, since they retain their viability for only a few days at room temperature. Even under the most favorable conditions, maximum storage is four to six weeks.

• Germination takes place 12 to 14 hours after planting. Keep soil moist while seedlings germinate and grow.

• When seeding outdoors, willows require moist soil from spring over-bank flows, capillary wetting of the soil surface, or irrigation for establishment.

Salix humilis (Prairie Willow)
(Insect visitors suck nectar; some bees also collect pollen from staminate flowers, as indicated below; a few observations are from Krombein et al. as indicated below, otherwise they are from Robertson; information about oligolegy in bees is from Krombein et al.)

On staminate flowers:

Bees (long-tongued)
Apidae (Apinae): Apis mellifera cp; Anthophoridae (Nomadini): Nomada dentariae sn, Nomada ovatus sn, Nomada sayi sn; Megachilidae (Osmiini): Osmia lignaria lignaria sn

Bees (short-tongued)
Halictidae (Halictinae): Augochlorella striata sn, Halictus rubicunda sn fq, Lasioglossum cinctipes sn fq, Lasioglossum forbesii sn, Lasioglossum foxii sn, Lasioglossum imitatus sn, Lasioglossum pilosus pilosus sn, Lasioglossum pruinosus sn, Lasioglossum versatus sn fq, Lasioglossum zephyrus sn; Colletidae (Colletinae): Colletes simulans armata sn fq; Andrenidae (Andreninae): Andrena barbilabris sn, Andrena bisalicis sn cp fq olg (Rb, Kr), Andrena carlini sn fq, Andrena cressonii sn fq, Andrena erythrogaster sn cp olg (Rb, Kr), Andrena erythronii sn fq, Andrena fenningeri cp olg (Kr), Andrena forbesii sn fq, Andrena hippotes sn, Andrena illinoiensis sn olg, Andrena imitatrix imitatrix sn fq, Andrena mandibularis sn, Andrena mariae sn cp olg, Andrena miserabilis bipunctata sn fq, Andrena salictaria cp olg (Kr), Andrena sayi sn

Wasps
Chrysididae: Chrysura pacifica

Flies
Syrphidae: Brachypalpus oarus fq, Eristalinus aeneus, Eristalis dimidiatus fq, Eristalis transversus, Eupeodes americanus, Helophilus fasciatus fq, Orthonevra nitida, Sphaerophoria contiqua; Conopidae: Myopa vesiculosa; Calliphoridae: Cynomya cadaverina, Phormia regina; Muscidae: Neomyia cornicina fq; Anthomyiidae: Delia platura; Sepsidae: Sepsis violacea fq; Scathophagidae: Scathophaga furcata fq

Butterflies
Nymphalidae: Nymphalis antiopa

Beetles
Orsodacnidae: Orsodacne atra; Coccinellidae: Hippodamia parenthesis; Lampyridae: Ellychnia corrusca

Plant Bugs
Miridae: Lygus lineolaris fq; Pentatomidae: Euschistus variolaria

On pistillate flowers:

Bees (long-tongued)
Apidae (Apinae): Apis mellifera fq; Apidae (Bombini): Bombus impatiens; Anthophoridae (Ceratinini): Ceratina dupla dupla fq; Megachilidae (Osmiini): Osmia lignaria lignaria

Bees (short-tongued)
Halictidae (Halictinae): Agapostemon sericea, Halictus confusus, Halictus rubicunda fq, Lasioglossum cinctipes fq, Lasioglossum forbesii, Lasioglossum versatus fq; Halictidae (Sphecodini): Sphecodes dichroa; Colletidae (Colletinae): Colletes simulans armata fq; Andrenidae (Andreninae): Andrena bisalicis fq olg, Andrena carlini fq, Andrena cressonii fq, Andrena erythrogaster olg, Andrena erythronii fq, Andrena forbesii fq, Andrena illinoiensis olg, Andrena miserabilis bipunctata fq

Wasps
Ichneumonidae: Colpognathus helvus, Ichneumon annulatorius

Sawflies
Tenthredinidae: Dolerus bicolor fq, Dolerus sericeus, Dolerus unicolor fq

Flies
Syrphidae: Brachypalpus oarus fq, Eristalis dimidiatus fq, Eristalis stipator, Eupeodes americanus, Helophilus fasciatus fq, Sphaerophoria contiqua; Calliphoridae: Cynomya cadaverina, Phormia regina; Muscidae: Helina rufitibia, Neomyia cornicina fq; Anthomyiidae: Delia platura; Sepsidae: Sepsis violacea fq; Scathophagidae: Scathophaga furcata fq

Plant Bugs
Lygaeidae: Lygaeus turcicus

Flower gender unspecified:

Bees (short-tongued)
Andrenidae (Andreninae): Andrena nigrae (Kr)

Barcode of Life Data Systems (BOLDS) Stats
Public Records: 4
Specimens with Barcodes: 4
Species With Barcodes: 1

Rounded Global Status Rank: G5 - Secure

Canada

Rounded National Status Rank: NNR - Unranked

United States

Rounded National Status Rank: NNR - Unranked

Please consult the PLANTS Web site and your State Department of Natural Resources for this plant’s current status, such as, state noxious status and wetland indicator values.

Prairie willow saplings are available from most nurseries in the areas where they grow. We recommend using plants from the same region, elevation, climate, soil type, moisture, or hydrologic regime as you are replanting.

Contact your local Natural Resources Conservation Service (formerly Soil Conservation Service) office for more information. Look in the phone book under ”United States Government.” The Natural Resources Conservation Service will be listed under the subheading “Department of Agriculture.”

Traditional resource management of willow includes the following:

• Willows were traditionally tended by pruning or burning to produce long straight stems.

• Willow is gathered only at certain times of the year, beginning in the autumn after the leaves fall. For many weavers, gathering will continue until the following spring when the sap begins to rise again.

• Often, basketweavers will prune many willows, sometimes replanting the stems, so there will be nice straight basketry materials the following year.

• Before gathering, the weavers make offerings of thanks and pray for permission to gather. Often tobacco or other offerings are given before beginning to gather.

• Basket weavers process materials with their hands and mouths. Herbicides sprayed on willows and along streams have a much higher health risk for humans when they are processed and used for traditional materials.

Howe and Knopf (1991) conclude that to ensure the survival of willows and cottonwoods in riparian communities, resource managers need to implement strategies to control the spread of exotic species.

Livestock grazing has widely been identified as a leading factor causing or contributing to degradation of riparian habitats in the western United States (Chaney et al. 1990, Fleischner 1994, Ohmart 1996). Livestock grazing can alter vegetative structure and composition of riparian habitat. Overgrazing, especially by livestock and big game, frequently changes plant species composition and growth form, density of stands, vigor, seed production of plants, and insect production. Livestock grazing can cause the replacement of bird and mammal species requiring the vertical vegetation structure of riparian habitat to species, which are ubiquitous in their habitat preferences. Previous heavy cattle grazing changed the bird and small mammal community composition in riparian areas through reduction of shrub and herbaceous cover.

Slovlin (1984) recommended a 5-year rest from cattle grazing to re-establish healthy stands of riparian vegetation such as cottonwood and willows. Siekert et al. (1985) reported that spring grazing showed no significant changes in channel morphology, whereas summer and fall grazing did. However, even with limited seasonal grazing, all tree seedlings would be eliminated. Marlow and Pogacnik (1985) recommended fencing riparian habitat, rest-rotation, light grazing (<20% forage removal), and grazing after streambanks have dried to 10% moisture.

Willows were used for making dye, furniture, mats, baskets, drums, stirrups, tipi pegs and pins, fox and fish traps, hunting lodge poles, and meat-drying racks (Kindscher 1992). Willows were and still are used for baskets throughout their range. The Paiute, Ute, Shoshone, Hopi, Havasupai, Mandan, Cheyenne, Arapaho, Kiowa, and others use Salix lucida for basketweaving (James 1972, Mason 1988).

Kelly Kindscher(1992) wrote in Medicinal Wild Plants of the Prairie: "The Blackfeet made a tea from the fresh root of Salix species to treat internal hemorrhage, throat constrictions, swollen neck glands, and bloodshot or irritated eyes. The twigs were also gathered and preserved. Steeped in boiling water, they were made into a tea to cure fever or alleviate pain."

Salix species were used as chew sticks to clean teeth by many other Indian tribes, including the Choctaw, Delaware, and Cheyenne. The prairie willow was favored by the Osage, Delaware, and Cherokee for this purpose (Elvin-Lewis 1979). The Kiowa made a tea of willow leaves, which they rubbed on the body to cure pneumonia and relieve rheumatic aches. They also chewed the bark to relieve toothaches (Vestal and Shultes 1939). The Comanche burned the stems of the willow and used the ashes to treat sore eyes (Carlson and Jones 1939). To restore themselves both physically and mentally, the Dakota drank a willow-bark tea (Andros 1883). The Ojibwe

used prairie willow bark externally to treat skin rashes.

Aspirin is the pharmaceutical equivalent of willow bark tea, which is an effective remedy for headache, fever or sore throat. More than 2,400 years ago, the Greeks learned to use extracts of several native willow species to treat pain, gout, and other illnesses. In more recent times, in 1839, salicylic acid was isolated from wild plants and manufactured synthetically. Early salicylic acid-based products had unpleasant side effects. Sixty years later, the Bayer Company developed a derivative of salicylic acid, called it aspirin, and the rest is history.

Tea made from willow leaves will cure laryngitis. Willow reduces inflammation of joints and membranes (Moore 1979). When used as an analgesic, willow treats urethra and bladder irritation, infected wounds, and eczema. Willow is used as an over-all treatment of many diseases, including hay fever, diarrhea, prostatitis, satyriasis, and as a relief of ovarian pain. A poultice is made for treating gangrene and skin ulcers.

Young willow shoots can be stripped of their bark and eaten. The young leaves may be eaten in case of emergency. The inner bark can be eaten raw, prepared like spaghetti, or made into flour.

Riparian: Riparian ecosystem functions provided by prairie willow include the following: 1) Riparian vegetation traps sediments and nutrients from surface runoff and prevents them from entering the aquatic system; 2) the dense matrix of roots in the riparian zone can serve as an effective filter of shallow groundwater; 3) water quality is improved through filtration and the trapping of sediment, nutrients (particularly nitrogen dissolved in groundwater), and pollutants; and 4) riparian areas act as a sponge by absorbing floodwaters. The water is then slowly released over a period of time, which minimizes flood damage and sustains higher base flows during late summer.

Wildlife: Structurally complex riparian vegetation communities provide many different habitats and support a diverse array of animal species. The multiple layers of vegetation provide multiple niches for many species of insects and wildlife canopies of plants growing on streambank provide shade, cooling stream water, while roots stabilize and create overhanging banks, providing habitat for fish and other aquatic organisms.

Rabbits and many ungulates (including deer, moose, and elk) browse on willow twigs, foliage, and bark (Martin 1951). Beaver love willow branches. Several species of birds eat willow buds and young twigs. Riparian forests support a high diversity of breeding birds (Miller 1951). The percentage of breeding individuals, which are migratory, is very high in the cottonwood-willow habitat. Moister conditions in the cottonwood-willow forest may promote lusher plant growth, higher invertebrate populations and, therefore, more available food for flycatchers, warblers, and other migratory, insectivorous birds. Riparian areas support up to 10.6 times the density of migrant birds per hectare as adjacent non-riparian areas (Stevens et al. 1977). Most of these migratory birds belong to the foliage insect (47%) or air insect (34%) foraging guilds.