Iowa Commercial Pesticide Appl:
Right-of-Way (Category 6)
Dicamba - correct answer-Vanquish is less volatile than Banvel, reducing the risk of
off-target movement, soybeans are very sensitive to Dicamba.
Effect of spray droplet size on drift - correct answer-Droplet diameter: 10 um travels 7,480 ft;
100 um travels 77 ft
Explain some ways to prevent damage to nontarget plants - correct answer-The majority of
problems encountered in right-of-way spraying involve the phenoxy or similar herbicides,
they are injurious to plants at extremely low rates;
the two principle mechanisms by which a herbicide moves off-target are drift & volatilization,
herbicides may also move off-target in runoff water or be carried away with eroded sediment.
Explain the Integrated Roadside Vegetation Management program - correct answer-The
object of IRVM is to establish & maintain a safe, stable, low-maintenance roadside that is
healthy & attractive for humans & wildlife. Stability is attained by the use of native vegetation,
county roadside managers (CRM) mimic the durable, diverse prairie plant community that
existed in Iowa for thousands of years, alongwith the use of native & non-native grasses &
wildflowers, CRMs are integrating several different vegetation management techniques, in
addition to traditional use of herbicides & mowing, CRMs also employ nontraditional
methods to invigorate & sustain the vegetative cover. Burning is one such method. During
the early spring CRMs will select several sites to conduct a planned or prescribed burn, it will
retard the growth of many invading weeds & invigorate the existing prairie plants. Other
important factors of IRVM are low maintenance & adjacent landowner cooperation.
Explain what drift is and what factors are responsible for problems encountered - correct
answer-Drift is the physical movement of spray droplets from the target site. The two primary
factors that effect the amount of drift are: spray droplet size & the wind speed;
Wind: problems at 5 mph, spraying should stop when wind exceeds 10 mph; Droplet size: as
droplet size decreases , the distance a droplet will travel off-target increases; select a nozzle
that produces an appropriate range of droplet sizes; as spray pressure is increased, the
range of droplet sizes produced will shift towards smaller droplets, operate the sprayer at a
relatively low pressure; also drift retardants can reduce the formation of small droplets, an
invert emulsion is a thick mixture of oil & water that has the consistency of mayonnaise,
specialized spray equip required.
Explain what herbicide runoff is and what factors are responsible for problems encountered -
correct answer-Herbicides also may move from the treated area in surface water runoff or in
sediment; the potential for herbicide loss is determined by many factors, including rainfall
events, amount of herbicide applied, & soil absorption characteristics of the herbicides;
herbicides are most vulnerable to runoff during the first rainfall event after application;
nonselective herbicides with a long soil residual should not be used in areas prone to runoff;
hard rain, problems; no vegetation, problems; herbicides with low soil adsorption & high
, water solubilities (e.g., Tordon) can move from treated areas in surface runoff in the absence
of soil erosion, don't use in sloped areas.
Explain what volatilization is and what factors are responsible for problems encountered -
correct answer-Volatilization, also known as vapor drift, is due to evaporation of the herbicide
after it impinges on the soil or plant. Herbicides that have a high vapor pressure are
susceptible to vapor drift whenever temperatures exceed 85F; herbicides that are prone to
volatilization include the phenoxy herbicides & dicamba; available as ester ( more effective,
more volatile) or amine products; Dicamba (Banvel) is especially prone to volatilization,
Clarity & Vanquish contain the diglycolamine (DGA) salt of dicamba (they have a lower vapor
pressure than Banvel); soybeans are particularly sensitive to dicamba.
Fosamine - correct answer-Krenite is applied in late summer to woody species & prevents
leafing out next spring. Complete coverage of tree is required for a total kill.
Glyphosate - correct answer-Roundup Pro is for noncropland & forestry use; Accord is for
use in forestry & utility right-of-ways; Rodeo is for aquatic use.
How can you use IRVM to manage a patch of noxious weeds that dominate a site? - correct
answer-Integrating several vegetation management techniques, such as frequent mowing
followed by a spot herbicide application in the fall, a spring burn followed by several
mowings, or three spot herbicide applications 30 days apart followed by a spring burn, may
be necessary to obtain weed control, a follow-up reseeding of desirable vegetation will be
necessary to establish a stable vegetative cover.
Imazapyr - correct answer-Arsenal & Stalker are intended for general noncropland use,
whereas Contain is registered for farmstead noncropland use. Stalker is cleared for
basal-bark & cut -surface treatments.
List other application techniques used for woody vegetation control - correct
answer-Short-term total vegetation control - nonselective herbicides are often used to
eliminate the need for trimming around signs, light poles & guard rails, the characteristics of
these chemicals vary widely - select the herbicide that best fits the need of a specific
situation, PARAQUAT (Gramoxone Extra) thorough coverage required, Paraquat does not
translocate, most perennials will quickly resume growth, is rapidly inactivated in soil & will
not provide any residual control, is restricted-use pesticide; GLYPHOSATE (Roundup
Ultra/Touchdown) is similar to paraquat in that it will provide complete burndown of all
vegetation with no residual control, Glyphosate is translocated within plants & will effectively
control many perennial plants. VELAR or ARSENAL can be used in areas where it is
desirable to prevent plants from quickly invading the treated area, combine the
characteristics of a nonselective burndown herbicide & a preemergence herbicide, length of
control varies, normally 1 to 6 months.
Long-term total vegetation control - soil sterilants, often used in storage yards, parking lots,
along pipelines, and in other areas where it is desirable to completely eliminate plant growth,
they should not be used in areas susceptible to erosion, if before rain chemical can be
eliminated by removing the first inch of soil, alternative mix activated charcoal into soil (3
pounds per 1,000 square feet of soil), trench & block tree roots
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller Hkane. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $7.99. You're not tied to anything after your purchase.
