Helianthus maximiliani, Maximilian sunflower
Walsh, Roberta A. 1993. Helianthus maximiliani, Maximilian sunflower.In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: https://research.fs.usda.gov/feis/species-reviews/helmax
| Abbreviation | Common Name | Scientific Name | Classification | Status |
|---|---|---|---|---|
| Plants | ||||
| HELMAX | Maximilian sunflower | Helianthus maximiliani | Life Form: Plants/Forb Kingdom: Plantae Class: Dicot Order: Asterales Family: Asteraceae Genus: Helianthus | Fed. Protected: No Nativity: Native Invasiveness: Noninvasive |
Taxonomy
The currently accepted scientific name of Maximilian sunflower is Helianthus maximiliani Schrad. [1,16,18,33]. It is a member of the sunflower family (Asteraceae). There are no recognized subspecies, varieties, or forms.
Synonyms
- Helianthus maximilianii Schrad. [17,20]
Other Common Names
Maximilian sunflower, Maximillian sunflower, Maximilian's sunflower
General Distribution
Maximilian sunflower is native to the Great Plains and adjacent areas [44]. It is found from Saskatchewan and Manitoba south to Missouri and Texas [17,18,22]. It has been sparingly introduced in the Pacific Northwest [20], California [30], and east to the Atlantic states [12].
States and Provinces
- United States: AL, AR, CA, CO, CT, ID, IL, IN, IA, KS, KY, ME, MA, MI, MN, MO, MT, NE, NM, NC, ND, OH, OK, SD, TN, TX, UT, WI, WY
- Canada: AB, BC, MB, SK
- Mexico
Site Characteristics
Maximilian sunflower occurs on dry to moist open prairie, often on sandy sites [17]. It is best adapted to deep, sandy to clayey loam upland soils of subhumid prairies [44]. Growth is poor on gravel and dense clay, fair on sand and clay, and good on sandy to clayey loam. Maximilian sunflower grows poorly on saline soils. Its optimum soil depth is 20 inches (50 cm) or more. It is more common on heavier soils [44]. It is also found on waste ground, roadsides, pastures [1], fence rows [33], riverbanks [18], and other disturbed areas [29].
Maximilian sunflower generally occurs in areas with 10 to 50 inches (250-1270 mm) annual precipitation [35], but it can occur on lowlands with better moisture conditions in the semiaric zones [44].
Maximilian sunflower exhibits good growth on gentle slopes and poor growth on moderate and steep slopes [10].
Maximilian sunflower occurs at the following elevations [10]:
| Location | Elevation (feet) | Elevation (m) |
|---|---|---|
| Colorado | 3,500-7,000 | 1,067-2,134 |
| Montana | 2,300-3,900 | 700-1,190 |
| Wyoming | 3,600-6,000 | 1,100-1,830 |
Plant Communities
Associates of Maximilian sunflower vary with location, since this species has a wide ecological amplitude and it occurs in a variety of prairie ecosystems.
Associates of Maximilian sunflower in mixed-grass prairie south of Lake Manitoba in Canada include little bluestem (Schizachyrium scoparium), big bluestem (Andropogon gerardii var. gerardii), alkali muhly (Muhlenbergia asperifolia), common witchgrass (Panicum capillare), Kentucky bluegrass (Poa pratensis), Russian thistle (Salsola kali), silverberry (Eleagnus commutata), showy milkweed (Asclepias speciosa), and western snowberry (Symphoricarpos occidentalis) [27].
Associates of Maximilian sunflower in undisturbed tallgrass prairie on Mormon Island on the Platte River in Nebraska include the dominant big bluestem, and lesser components switchgrass (Panicum virgatum), Indian grass (Sorghastrum nutans), heath aster (Aster ericoides), western ironweed (Vernonia fasciculata), and Canada goldenrod (Solidago canadensis) [8].
Associates of Maximilian sunflower in floodplain tallgrass prairie in a wetlands area in Kansas include prairie cordgrass (Spartina pectinata), ovoid spikesedge (Eleocharis obtusa), Indian grass (Sorgastrum nutans), big bluestem, switchgrass, sedge (Carex frankii), common sunflower (Helianthus annuus), compass plant (Silphium laciniatum), hemp dogbane (Apocynum cannabinum), common milkweed (Asclepias syriaca), and thickspike gayfeather (Liatris pycnostachya) [7].
Botanical Description
Maximilian sunflower is a warm-season, bunching, perennial native forb [44]. It grows 1.6 to 8.2 feet (0.5-2.5 m) tall [17], with a spread of 1 to 3 feet (0.3-0.9 m) [21]. Stems grow singly or clustered from short rhizomes [44]. The flowers occur in long, raceme-like inflorescences [15]. The floral head is 1.5 to 3 inches (4-8 cm) wide [1]. The fruit is an achene 0.12 to 0.16 (3-4 mm) long [17]. Maximilian sunflower has short, thick, rhizomatous rootstocks [17] with crown-buds [15].
Raunkiaer Life Form (Raunkiaer 1934)
- Hemicryptophyte
- Geophyte
Seasonal Development
Maximilian sunflower seeds germinate best when soil is warm [31], generally in May throughout much of the area in which it occurs. Stands develop rather rapidly from seed. Growth occurs in late spring and summer [43], with some flowering possible by the end of the first growing season in the South. However, plants are not usually fully developed until the second year [44]. Maximilian sunflower dies back to the ground each year, and regenerates new growth from rhizomes or root crown buds [43]. Plants continue to spread by rhizomes after establishment [44].
Maximilian sunflower flowering times are:
| Location | Begin flowering | Peak flowering | End flowering |
|---|---|---|---|
| Colorado | June | August | September |
| Illinois | July | — | August |
| Kansas | August | September | October |
| Montana | July | July | September |
| North Carolina | September | — | October |
| North Dakota | July | August | September |
| South Dakota | July | — | September |
| Wyoming | July | July | September |
| Great Plains | August | — | October |
| New England | August | — | September |
Regeneration Processes
Maximilian sunflower is a perennial which reproduces by seed [31,43]. It also spreads vegetatively by rhizomes, and can form large colonies [44].
Maximilian sunflower cultivar "Aztec" seeds germinate within 1 to 3 weeks with a germination temperature regime of 12 hours each day at 86 degrees Fahrenheit (30 deg C) or lower [31]. With other seed sources, germination can occur in 7 to 14 days, but nearly half can be dormant. Seedling vigor is good [44].
Maximilian sunflower seeds from the soil bank at 22 typical habitats in Kansas were collected in November, 1945, and stored in cool, dry conditions until February, 1946. Subsequent germination tests showed two major periods of germination: one between days 6 and 25, and another between days 46 and 55 [26].
Successional Status
Facultative Seral Species
Maximilian sunflower thrives in sunlight and has only fair shade tolerance [44]. Stand longevity can be 5 or more years [9].
Immediate Fire Effects
Maximilian sunflower is probably top-killed by fire during the growing season. It survives by sprouting from persistent rhizomes [17,44].
Postfire Regeneration Strategy (Stickney 1989)
- Rhizomatous herb, rhizome in soil
- Initial-offsite colonizer (off-site, initial community)
- Secondary colonizer - off-site seed
Fire Adaptations
Maximilian sunflower has good fire tolerance in the dormant state, and can reproduce by rhizomes [44]. It produces numerous, small, wind-dispersed seeds which germinate over a wide range of temperature and moisture regimes [38] and can establish on burned sites. Maximilian sunflower thrives in the open, sunny conditions created by fire [14]. Maximilian sunflower seeds have been found in the seedbank [26], and it may be an initial on-site colonizer, but no information was available on seed tolerance to heat or length of seed viability in the seedbank.
Plant Response to Fire
Fire usually enhances Maximilian sunflower, probably by removing litter, allowing more sunlight to reach the soil surface, and reducing competition.
Maximilian sunflower was burned in prescribed fires in May, 1970 and May, 1971 in east-central North Dakota. It increased in cover more than 100 percent within the first 2 postfire years [23].
When dead vegetation mulch was burned in North Dakota in 1968 and 1969, Maximilian sunflower and other plants grew taller, stiffer, and seeded more vigorously [40].
Tallgrass prairie sites containing Maximilian sunflower in northwestern Minnesota were subjected to prescribed fire in early May, 1972. The removal of litter by fire varied with the site. In undisturbed prairie on a mesic site, flowering decreased significantly following fire. On a wet-mesic site in highly disturbed prairie, there was a slight, nonsignificant decrease in flowering. On a wet swale in undisturbed prairie, there was a very significant increase in flowering [32].
Fire Regimes
For fire regime information, search FEIS for this species by entering the species name or acronym on the home page and selecting “Fire Regime” as the publication type.
Fire Management Considerations
In southwestern Minnesota, a degraded prairie that had been invaded by shrubs and cool-season grasses was burned each spring from 1983 to 1987. Native warm-season grasses and forbs, including Maximilian sunflower, increased in dominance, and the prairie became more open each year. Maximilian sunflower showed increased vigor, and new individuals were established [2].
In the High and Rolling Plains of Texas, prescribed fire is used every 3 to 5 years to maintain optimum quail habitat in the grass stands where Maximilian sunflower occurs [6].
In the Northern Great Plains, the best increases in Maximilian sunflower vigor, canopy cover, and seed production are obtained with late spring (May-June) fires [19].
Federal Status
None
Other Status
No entry.
Importance to Wildlife and Livestock
Maximilian sunflower is part of the tall, thick, ungrazed cover in North Dakota that ducks and pheasants seek out for nesting. It also provides winter cover and its seeds are an important winter food [40].
In Montana, Maximilian sunflower is rated as valuable fall forage for Rocky Mountain elk [25].
Palatability and Nutritional Value
Maximilian sunflower is a palatable livestock forage of good quality, [22], and is also used by deer [44]. It remains green after many other forbs have matured [22], but little use is made of the herbage after frost [44]. The seeds are choice food for quail and dove [42], and are eaten by many other birds [44].
Maximilian sunflower palatability for livestock in several western states is as follows [10]:
| Species | Colorado | Montana | North Dakota |
|---|---|---|---|
| Cattle | Fair | Fair | Good |
| Domestic sheep | Fair | Fair | Fair |
| Horses | Fair | — | Good |
Maximilian sunflower energy value for livestock is fair. Protein value is poor [10].
The food value of Maximilian sunflower for several species of wildlife in some western states is as follows [10]:
| Species | Colorado | Montana | North Dakota | Wyoming |
|---|---|---|---|---|
| Elk | — | Poor | — | Good |
| Mule deer | — | Poor | Good | Poor |
| White-tailed deer | — | — | Good | Poor |
| Pronghorn | Poor | — | Good | — |
| Upland game birds | — | — | Fair | — |
| Waterfowl | — | Poor | Poor | — |
| Small nongame birds | — | — | Good | — |
Cover Value
The cover value of Maximilian sunflower for several species of wildlife in some western states is as follows [10]:
| Species | North Dakota | Wyoming |
|---|---|---|
| Elk | — | Poor |
| Mule deer | Fair | Poor |
| White-tailed deer | Fair | Poor |
| Pronghorn | Fair | Poor |
| Upland game birds | Fair | — |
| Waterfowl | Poor | — |
| Small nongame birds | Fair | — |
Value for Rehabilitation or Restoration of Disturbed Sites
Maximilian sunflower was determined by the Soil Conservation Service Plant Materials Center in Kansas to be appropriate for use in rehabilitation of degraded sites and for visual enhancement. In field tests it showed excellent vigor [21].
Maximilian sunflower has been used successfully for revegetation of coal mine spoils in Kansas. It established with native grasses on abandoned spoils graded to rolling topography, limed, and disced [43].
The Soil Conservation Service recommends Maximilian sunflower cultivar "Aztec" for use in rehabilitation in southern Oklahoma, all of Texas except the Trans-Pecos region, and eastward. The cultivar "Prairie Gold" has greater cold tolerance, and can be used for revegetation farther north [44].
Maximilian sunflower is suggested for use on roadsides, in parks, for wildlife habitat, and in establishing prairies [37].
Other Uses
Maximilian sunflower roots can be prepared and eaten like those of Jerusalem artichoke (Helianthus tuberosus). Native American tribes of the Great Plains ate them raw, boiled, or roasted [28].
Maximilian sunflower was evaluated as a potential source of industrial raw materials. Since the natural rubbers present are of low molecular weight, they may have commercial applications [35].
Maximilian sunflower is used as a garden ornamental [28].
Other Management Considerations
Planting for wildlife: Maximilian sunflower has been planted for cover and as a food source for scaled quail, northern bobwhites, and mourning doves in the High and Rolling Plains of Texas [6]. It is a good addition to a mix of shrubs, forbs, and grasses for use as wildlife habitat [42].
Planting for prairie establishment: Due to its aggressive spreading, Maximilian sunflower should be lightly seeded in prairie grass mixtures. Optimal seeding times are November to May in the Central Great Plains, and January to March in the Southern Great Plains. Early planting may aid in breaking seed dormancy [44]. Maximilian sunflower requires low to moderate moisture and full sun [37]. It was included in a mix of native prairie grasses and forbs used to establish prairie on previously cultivated fields in eastern Nebraska from 1975 to 1978. It proved to be susceptible to herbicides, and established best when mechanical means were used to control weeds [5].
When buckthorn (Rhamnus cathartica) in Minnesota was removed by cutting and stump treatment with herbicide in 1985, Maximilian sunflower, which had not been present, germinated in treated areas within 3 months of initial treatment [4].
Maximilian sunflower was evaluated and grown at the Soil Conservation Service Plant Materials Center in Kansas. Planting procedures are described [9]. Maximilian sunflower seed accessions are held at the wild sunflower (Helianthus spp.) nursery of the Plant Introduction Station in Ames, Iowa. The collection can be used for problems in prairie establishment or restoration [45].
Grazing: Maximilian sunflower is not common on closely grazed ranges. Seedlings should be protected from close use and trampling. Moderate grazing and periodic deferment of grazing during the growing season enhance the persistence of Maximilian sunflower [44].
Table A1— Forest and range ecosystems, Bureau of Land Management (BLM) physiographic regions, Kuchler plant associations, Society for American Foresters (SAF) forest cover types, and Society for Rangeland Management (SRM) rangeland cover types in which this species occurs.
Forest and Range Ecosystems (Garrison et al. 1977)
- FRES15 Oak – hickory
- FRES17 Elm - ash – cottonwood
- FRES21 Ponderosa pine
- FRES29 Sagebrush
- FRES31 Shinnery
- FRES34 Chaparral - mountain shrub
- FRES35 Pinyon – juniper
- FRES38 Plains grasslands
- FRES39 Prairie
BLM Physiographic Regions (Bernard and Brown 1977)
- 10 Wyoming Basin
- 11 Southern Rocky Mountains
- 13 Rocky Mountain Piedmont
- 14 Great Plains
- 15 Black Hills Uplift
- 16 Upper Missouri Basin and Broken Lands
Kuchler Plant Associations (Kuchler 1964)
- K016 Eastern ponderosa forest
- K023 Juniper - pinyon woodland
- K037 Mountain-mahogany - oak scrub
- K056 Wheatgrass - needlegrass shrubsteppe
- K064 Grama - needlegrass – wheatgrass
- K065 Grama – buffalograss
- K066 Wheatgrass – needlegrass
- K067 Wheatgrass - bluestem – needlegrass
- K068 Wheatgrass - grama – buffalograss
- K069 Bluestem - grama prairie
- K070 Sandsage - bluestem prairie
- K071 Shinnery
- K074 Bluestem prairie
- K075 Nebraska Sandhills prairie
- K076 Blackland prairie
- K081 Oak savanna
- K084 Cross Timbers
- K098 Northern floodplain forest
SAF Cover Types (Eyre 1980)
- 40 Post oak - blackjack oak
- 42 Bur oak
- 62 Silver maple - American elm
- 67 Shin (Mohrs) oak
- 220 Rocky Mountain juniper
- 237 Interior ponderosa pine
- 239 Pinyon – juniper
- 241 Western live oak
SRM Rangeland Cover Types (Shiflet 1994)
- No entry
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