Personal settings is a facility available to Pro and Pro Plus subscribers. This facility enables you to save and later reuse information from your own fields, your own customers or your imagined scenarios (combinations of crops, herbicides, weeds etc.). A selected personal setting will persist, also when you switch between tools. Press the link, select Edit to Add, Rename or Delete your Personal settings. For subscribers to Basic, only 1 Personal setting will be available and cannot be edited.
Crop, Undersown and Season
The competing ability of crops (including possible undersown crops) against weeds influences the efficacy targets in IPMwise, and the options for control (herbicides and mechanical control) available.
Season separates Autumn from Spring/summer and is defined by calendar dates. Season ensures a correct handeling of crop growth stages, which may occur both in the autumn and in the spring.
Crop growth stage
The crop growth stage determines available options for control (herbicides and mechanical control). To avoid confusion, only growth stages where control measures are available, are shown. Many weeds will often only be listed in early growth stages where many options for control are available (sufficiently effective). In many newer registrations of herbicides (labels), the allowed max. doses increase with increasing crop growth stages, while the susceptibility of weeds drop accordingly, due to the larger growth stages also of weeds.
Information on expected yield is only requested in cereal crops. An expected, relatively low level will affect the expected competition with weeds, which is compensated by slight increases in effiacy targets of IPMwise. In Danish cereals low yield levels are defined like this:
- spring cereals: < 50 hkg/ha
- winter cereals: < 60 hkg/ha
The growth stage of weeds affects the efficacy of herbicides. In general, small seeded weeds are more susceptible than bigger plants, while perennial weed species (germinating from roots) are often more susceptible (to achieve long term control), when they have developed enough leaves to ensure also considerable translocation to root system, i.e. when minimum 3-4 leaves have been developed. Field inspections shall be made for seeded weeds, as soon as species can be determined, i.e. when plants have about 1-2 true leaves.
Water stress (weeds)
Drought stress implies that the expected efficacy of herbicides will be reduced drastically. However, drought stress, is only rarely seen in Denmark, and usually not on small weed plants at all. As long as weed leaves bristle as normal, water stress (affecting herbicide efficacy) is not expected. Drought stress may be detected from visual symptoms on weed plants, e.g. characteristic hanging or curling leaves. In case of water stress, herbicide dose rates often need to be indreased by 50%-500% to maintain efficacy levels. In such cases, maximum dose rates are likely to be exceeded, why a reasonable recommendation will be to wait for rain or a shower.
Minimum and maximum temperatures
The temperature before, during and after herbicide application may influence efficacy, where the temperture close to the time of application has the dominating influence. For most herbicides, increasing temperatures will lead to increased efficacy (as long as no severe drought stress is present). Min- and max. temperatures refer to the day of herbicide application. Even in extreme temperatures, adjustments of herbicide doses rates will often only be in the range +/-10-15%.
In top of the section presenting recommendation, your entered conditions for calculation is presented. You may choose, which details you wish to include in the ouput, e.g.:
- expected effiacy of 5 fixed dose rates(1/8, 1/4, 1/2, 1/1 og 2/1 of max. dosis)
- efficacy targets at 8 classes of weed density (from Few plants in field up to > 600 plants/m2)
- doses, which canmeet efficacy targets. Doses exceeding max. doses are shown in red color.