The distribution of dry matter between the above- and below-ground parts of a plant does not account for these differences at the seedling stage, however, which is also the case for annual and perennial plants . Based on initial seedling growth, all fescues , with the exception of Kentucky bluegrass, showed a greater accumulation of dry matter, biological productivity and growth rate within the first 5 weeks when compared to the nimblewill, showing that nimblewill has a slower developmental stage and can be suppressed by pastures in field conditions. In general, the first plant to take root has a better chance in competing for environmental resources. However, bluegrass showed an accumulation of dry matter that was less than that of the weed, indicating that the bluegrass and pasture may suffer from competition with the nimblewill. In another experiment, found that bluegrass grows much slower than other species. Those species that grow faster would be able to preempt the uptake of growth resources and, thus, would be expected to be more competitive . Control of spreading nimblewill is usually attempted with a nonselective systemic herbicide, when the weedy plants are young.
The mother plants are easily killed but, oftentimes, the weed will return, growing from the stolons; thus, an additional application of the herbicide is recommended.One must weigh the advantages and disadvantages before deciding whether to attempt control measures. Knowledge of the best stage during weed development to apply a control measure may increase the effectiveness of management strategies. Information on nimble will growth rates can be used to estimate the optimum period for post-emergence weed control with herbicides and the optimum timing of herbicide application or cultural control in conventional planting. Although riparian areas comprise less than 2% of the land area in the arid and semiarid western United States, they contribute disproportionately to physical and biological processes. They serve as pathways for the flow of energy, matter,cannabis grow equipment and organisms through the landscape, acting as ecotones between the terrestrial and aquatic zones and corridors across regions . Riparian vegetation plays important roles in trapping soil eroded from uplands and removing nutrients from surface and soil water , stream morphological dynamics , and aquatic, avian, and large game habitat requirements . Since the late 1800s, dry land small grain production has been practiced on nearly all the arable land of the inland Pacific Norwest .
Before widespread motorized mechanization of farming practices in the 1940s, the bottomland of second and higher order streams in this region were used extensively for grazing livestock, particularly draft horses, mules, and oxen. Beginning in the 1940s, much of this bottomland was converted to small grain production, resulting in the elimination of natural stream channels and riparian areas and the disruption of flood plains. Infrastructure maintenance requirements, the need for farm operation efficiency, and government incentives led to the channelization of many of the streams in this region. Channelization creates steep banks unprotected by vegetation cover or consolidating root structure. Deep, channelized storm flow saturates unprotected stream banks, creating positive pore pressures that cause bank failure when the storm flow recedes , and concentrates energy to transport soils eroded from uplands, stream banks and bottoms to deposition areas.
Whereas the goal of stream channelization is to drain soil water more efficiently, the effect is to disconnect the hydrologic flux between stream channel and adjoining land. In forest or rangeland situations, this change in hydrology facilitates the establishment of opportunistic weed species. In croplands, the rapid draining of soil water short-circuits chemical and biochemical processes that would occur if the water were resident longer. For example; if water is stored in a floodplain from 2 to 10 days, nitrate concentrations would be reduced through denitrification . Functioning riparian areas are necessary to create multifunctional production systems as described by Jordan et al. . Until the late 1990s, efforts to restore or rehabilitate riparian areas occurred primarily in forests and rangelands on public lands through the efforts of USDA Forest Service, USDI-Bureau of Land Management, and USDI-National Park Service, with smaller scale private land projects sponsored by nongovernmental organizations such as The Nature Conservancy.