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The Modern Landscape And Increased Runoff

For thousands of years the Iowa landscape was dominated by tall grass prairievegetation that had deep root systems. The tall grass prairie helped form deeprich soils. Prairie soils had high organic matter content and plenty of pore space

between soil particles. These soil characteristics helped the prairie absorb andin ltrate most rainfall and shed little runoff.

As the prairie was converted to agriculture and cities were established, the abilityof Iowas land to absorb and in ltrate water decreased. Tillage-based agriculturereduced the organic matter content that had developed under the prairie. Organicmatter content gives the landscape the ability to act like a sponge. As organicmatter declined, runoff increased. Modern soils have less pore space for waterstorage which means more runoff.

Urban landscapes have impervioussurfaces (streets, parking lots, roof tops).Urban soils are compacted by gradingactivities associated with development.Impervious and compacted urban surfacesprevent in ltration and increase theamount of runoff. Urban runoff occurs withevery rainfall event, causing water qualityproblems and stream corridor erosion andincreased ood potential.

THe Benefits of Native Landscaping

The use of native plants in our modern landscapes helps connect us to our prairieheritage. Once established, native plants are aesthetically pleasing and requireless maintenance. They dont need watering or much fertilization, and mowingmay be reduced or eliminated. The reduced maintenance can lead to signi cantcost savings when compared to high maintenance turfgrass systems.

Native landscaping attracts desirable species, such as songbirds, dragon iesand butter ies. Native landscaping around urban ponds helps reduce problems

associated with geese, which prefer mowed turf. But most importantly,native landscaping will help restore soil quality over time, and helplandscapes absorb more rainfall and reduce the amount of runoff

from urban landscapes.

Native Landscaping

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Native plants can be used in anygarden or landscape theme. Useplugs or potted plants for fasterstablishment.

lugs, Plants, Seeds

Plugs are small plants that are

conomical to use but requiremore nurturing until established.They will need to be wateredegularly until the deep roots arestablished at least through therst growing season.

Plants are available in pots thatrange from 3 inches to one gal -lon in size. They provide showyblooms in the rst year.

Seeding isnt recommended ina garden setting. Seeding takesabout 3 years for the plants toestablish and become showy. Theappearance of a seeded gardenis more random and less groomedthan traditional landscaping.

Selecting Species

Select species adapted to thesoils, moisture regime and sun -

light characteristics. Open andsunny areas will support a largevariety of plants. Shady sites tendto have fewer species to choosefrom.

Gardens planted to water-lovingnatives will eliminate mowing onwet areas that tend to be ruttedwith mower tracks. If you havesteep slopes that are hard to mow,create a garden of native plantsthat wont need mowing.

Usually its best to select speciesthat are shorter growing (3 feet orless). Some native species growto 6 or 8 feet tall. In a small ower garden setting some of the tallerspecies op over and becomeunsightly.

Spacing

Typically plants should be spacedabout 1 foot apart. Place 2 inchesof mulch to help suppress weeds.Be prepared to weed until plantsare fully established. If using

plugs, spread the mulch rst andplant through it.

Maintenance

After establishment, maintenancewill be minimal. No fertilization orpesticide is needed. Remove deadvegetation each year by mowingand raking or by burning deadresidue. Be careful not to ignite

mulch if using re management.

Native Gardens

A beautiful ower garden planted tonative prairie species.Plugs

A backyard garden featuring native plants that provide a colorful display to the

neighboring surroundings.

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Native TurfAnother native landscaping options the use of native turf. Native turfeatures a blend of low-growing

native grasses that provide aawn-like appearance. A blend

of blue grama, buffalograss, andideoats grama is recommended.

Native turf provides deep, brousoot systems that will help buildnd maintain soil quality. Nativeurf is only adapted to well drainedites.

Growth

Native turf grasses are warm-eason plants, which means they

espond to the increased sunlights days grow longer and hot -er. Therefore, native turf will not

break dormancy and green up asarly in the spring as cool seasonurf grass lawns. However, they

will be green and growing in theummer when non-native cooleason grasses often go dormantn reponse to hot, dry conditions.

Management

Native turf requires a manage -ment regime that differs fromnon-native turf. It will not needertilization or watering after theoot systems are established.

Mowing of native turf plantingsould be eliminated, and the

height of the vegetation wouldtay in the 8 to 18-inch range.

Mowing could also be done on aimited basis, keeping the appear -nce of the natives more like tra -

ditional turf grass. Sideoats gramawill grow to about 18 inches, if ahorter growing blend is preferred,

use blue grama and buffalograss.

A turf border planted to buffalo and blue gramma prairie grasses that accentuatesan area planted to native prairie owers.

This landowner converted a portion of her yard into native turf to reduce watering demands.

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To reduce the costs of mowingarge expanses of turf such ascorporate campus, establishdiverse native planting usingmixture of native seeds. It will

probably take about three yearsor the native planting to becomeully established.

ite preparation

Kill existing vegetation prior toeeding prairie. When killing exist -ng vegetation, leave a border ofurf. Maintaining a mowed border

will provide a managed look to thenative landscape and will serves re breaks for prescribed burn

management. Broadcast or drill inhe seed.

management

Native plants spend the rst twoyears developing roots. Annualweeds usually can dominate anew planting. Keep competingvegetation mowed to a height of6 to 8 inches to allow sunlight to

reach the small natives. By thethird year the natives shouldourish and start to out-competeweedy plants.

Native landscaping reduces main -tenance but is not maintenance

free. Certain activities need to be

done on an annual basis; pre -scribed burning, spot treating ormowing for weed control, andcutting and stump treating woodyspecies that will encroach if youdont burn. The result of theseefforts will be an attractive native

prairie planting.

RESOURCES

Iowa Living Roadway Trust Fund Plant Identi er: www.iowalivingroadway.com/IowaPlants.asp

Iowa Native Lands: www.prrcd.org/inl/mission.htm Iowa Prairie Network: www.iowaprairienetwork.org/

Native Prairie Reconstruction

rochure created by the above partners and funded in part by the Iowa Living Roadway Trust Fund.

This reconstructed prairie was mowed sevearl times during the rst several yearsof establishment for weed management and is now maintained with periodic burns.The seasonal natural beauty is enjoyed by many.

Rainscaping Iowa is a statewide partnership effortpromoting methods & practices to create functionallandscapes that protect & improve water quality.

www.rainscapingiowa.org

CONTRIBUTIING PARTNERS

hotos provided by:DALS-DSC; ISWEP; LRTF; and Polk SWCD

he USDA is an equal opportunity provider and employer.