Prairie wild rose is a minor subdominant component of healthy mixed grass prairie plant communities. Prairie wild roses can grow in sandy, shallow, silty, and clayey ecological sites; it shows a strong preference for the sandy and shallow sites and has problems growing in the silty and clayey sites.
Each year prairie wild rose resumes growth during mid to late April. Vegetative growth in height continues during May and June. Flower buds appear during late May to early June. The flower period (anthesis) occurs during mid June to late July. Stems protected from grazing reach maximum mature height of 50 cm (20 in) during late July. Stems growing in fall grazed pastures reach mature heights of 13.0 cm to 25.0 cm (5.1 in to 9.8 in) and stems growing in summer grazed (early June to mid October) pastures reach mean height of 15.4 cm (6.0 in) with a range of 11.2 to 19.9 cm (4.4 in to 7.8 in).
Mean grazed stem weights on sandy sites were 0.92 g, on shallow sites were 0.65 g, on silty sites were 0.57 g, and on clayey sites were 0.59 g.
Following pollination by insects, seeds, and fruits develop. The fruits (hips) are retained on the plant through winter; wild roses do not have a seed shedding phenological stage towards the latter portion of the growing season. Senescence of rose stems usually begins in mid July and progressively increases as the growing season advances. Low precipitation events can increase the rates of dryness. The stems of prairie wild rose die back partly or completely to ground level during the winter.
Prairie wild rose stem abundance greatly increased under two conditions. During the severe drought of 1988 and the low precipitation during 1989 to 1992, grass growth and development greatly decreased, however, during the same five year period, prairie wild rose was able to increase in abundance as a result of the plants extensive root system and deep descending vertical roots. Rose stem abundance also increased when the integrity of the grass community had degraded. Grass plants produce double the leaf biomass than the plants need for photosynthesis to survive. The extra quantity of leaf biomass needs to be removed annually or the litter accumulates as mulch and standing dead that restricts water and sunlight from reaching the soil surface. These conditions cause degradation of the grasses with reduced biomass production, decreased grass density, and reduced belowground resource uptake of water and nutrients. After 12 to 20 years without grazing, the grass plants lose their competitiveness that permits the prairie wild rose plants to greatly increase in stem abundance on the nongrazed and ungrazed sites.
Prairie wild rose stem abundance decreased under two conditions. The replicated shallow ecological sites of the long-term nongrazed treatment have consolidated parent material within less than 30 cm (12 in) of the soil surface that is much harder than that under the shallow sites of the seasonlong and twice-over treatments. Long-term nongrazing not only causes plant community degradation but also causes problems with soil structure that prevents or restricts root penetration resulting in greatly decreasing wild rose stem abundance. The second condition was annual grazing by both the traditional seasonlong and biologically effective twice-over rotation treatments caused rose stem abundance to decrease. All of the prairie wild rose stems growing in native rangeland pastures were grazed. Grazed rose stems do not develop through the natural phenological growth stages and stop progress at the vegetative stage or at the post anthesis stage. The quantity of leaf area remaining on grazed rose stems is inadequate to replace expended carbohydrates. Many grazed rose stems attempt to produce short branches with leaves on the lower portions of remaining stems which almost always do not develop past the open bud stage. These conditions result in the reduction of prairie wild rose stem abundance.
For more information Go To:
https://www.ndsu.edu/agriculture/ag-hub/publications/dickinson-rec-2016-annual-report
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