by Todd Rutherford
As gardeners in Colorado may well know, our climate and altitude make for challenging growing conditions. This doesn’t mean we are completely immune from invasive exotic plants making an unwelcome home here. We do not have the burden that gardeners in wetter and warmer states may have at stopping the spread of invasive plants, but there are a few species you should be aware of so you can help stop these unwanted guests from gaining a foothold in our landscapes.
Why be concerned about invasive plants? They crowd out native plants, propagate uncontrollably, and may reduce forage for wildlife. Some may have a negative impact on your garden plants. And research suggests that some invasive species may pose dangers to humans through the increased risk of flooding due to damaged waterways, or increased fire danger.
The two worst invasive woody plants for Colorado and the surrounding region are the Russian Olive and the Tamarisk. Russian Olive (Elaeagnus angustifolia), is native to western and central Asia. It was introduced into North America in the latter part of the 1800’s. It is not related to true olive plants (Olea europaea) but its fruit is edible but not very palatable for human consumption. It out competes native plants because its seeds are irresistible to birds which spread the seeds far and wide. The seeds have a low mortality rate, germinate readily in poor soil (it can fix its own nitrogen in its roots), reach maturity quickly and thus outcompete native plants. In Colorado, they often begin setting a foothold in riparian areas, and then spread from there.
Russian Olives invading a wetland in New Mexico.
Tamarisk (Tamarix ramosissima), which is more of a shrub than a tree, similarly starts its spread in the riparian areas of the Colorado and other southwestern states. It has been such a successful invader of wet areas, that it has overtaken huge sections of the rivers of the southwest. However, it is not as tolerant of cold temperatures as is Russian Olive, which restricts its spread to the warmer, lower elevations of the southwest. Tamarisk is tolerant of many soil types, and thrives in full sun. One of the concerns about Tamarisk’s effect on native landscapes is how they out compete native vegetation, altering the nutrient cycles of riparian areas. They also consume large amounts of water, and secrete large amounts of salt, both items further slowing the success of nearby native plants. A massive amount of resources and manpower are being directed at the fight to stop the spread of this plant through the wildlands of the desert southwest.
…the Siberian Elm is “one of, if not the, world’s worst trees…a poor ornamental that does not deserve to be planted anywhere”.
Closer to Denver and the urban areas of Colorado’s front range, there are two trees that are common pests. These are the Siberian Elm (Ulmus pumila), and the Tree of Heaven (Ailanthus altissima). Both of these trees release a profuse amount of seeds, and these seeds are very adept at sprouting in disturbed areas. They proliferate along transportation corridors and abandoned lots. Both trees prefer full sun, but Ailanthus can tolerate some shade allowing it to invade some mature native forests.
Young Ailanthus altissima
Although not directly related, Ailanthus trees (a.k.a. Tree of Heaven) are often mistaken as sumacs. In springtime they produce many flowers that have a foul odor which some say is similar to cat urine. It rapidly out competes other tree species, releasing an allelopathic chemical which inhibits the growth of other plants. Some researchers have extracted this chemical from Ailanthus trees, successfully using it as an herbicide. Not only is this tree toxic to other plants, there have been anecdotal reports of it being slightly toxic to humans and livestock. Ailanthus trees can grow quite rapidly, leading to weak, unstable branches.
Siberian Elms also have structural problems, with many weak or dead branches that can break off in heavy wind. Siberian elms have a short dormancy period which leads to early flowering in spring, and late leaf drop in fall. In Colorado that means they can become dangerously loaded with wet snow in our common heavy spring snowstorms, or the occasional fall snowstorm, leading to heavy branches falling on roofs and vehicles. In addition to the dangers of breaking limbs, the trees do not have a very favorable appearance, with an awkward branching pattern. One doesn’t need to search too long before you find many Siberian elm seedlings sprouting up in unwanted spots in the urban landscape. The sprouts show up in shrub beds where they are difficult to remove by hand and hard to spray with herbicides without damaging neighboring desired plant materials. Siberian elms are susceptible to damage from elm leaf beetles which leave the leaves looking skeletonized, but it doesn’t seem to kill the trees. Notable horticulturalist Michael Dirr says the Siberian Elm is “one of, if not the, world’s worst trees…a poor ornamental that does not deserve to be planted anywhere”.
To be fair, I should mention that some people look favorably upon these four tree species, and say that in Colorado’s high desert climate (that is naturally and predominantly tree-less east of the Rocky Mountains), an invasive tree is better than no tree, especially in urban areas. I would beg to differ, noting that these trees are too difficult to control and remove, to the detriment of native flora and fauna. Please become aware of these invasive trees and be considerate about whether you want to allow these in your landscape.
This is the official blog of Outdoor Design Group, Colorado Landscape Architects. For more information about our business and our services, click here.
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by Matt Corrion
The drought of 2002 was very hard on landscaping in Colorado. Plants and lawns were stressed by the hot and dry conditions, and mandatory watering restrictions were put in place across the state. Many of us in the landscaping industry vividly remember these hard times.
Well, the drought is back. Today the USDA predicted a huge drop in corn yields, the latest is a long summer of bad drought news. Below are maps issued by the U.S. Drought Monitor from back in July of 2002 and from July of 2012. As you can see, there are many similarities and much of Colorado is once again in an “extreme drought” situation.
Outlook Does Not Look Good
According to the National Weather Service Climate Prediction Center, the U.S. Seasonal Drought Outlook doe not look promising, although some improvement may occur in southwestern Colorado:
Dryness and drought, exacerbated by above-normal temperatures, have been increasing both in extent and intensity across much of the central and northern U.S. Based upon the July 24 U.S. Drought Monitor, almost 64 percent of the contiguous U.S. was in drought (D1-D4), the highest such value for the U.S. Drought Monitor since its inception in 2000. The last time the lower 48 States had a comparable area of drought (based upon the monthly Palmer Drought Index) was in 1956, according to NCDC.
Across the Southwest, the odds favor an active (wet) southwest monsoon in both the 1- and 3-month precipitation outlooks. As a result, improvement is anticipated across much of Arizona, southern Utah, and southwestern Colorado as the summer monsoon continues.
What Does this Mean for Landscaping in Colorado?
As these maps illustrate, the drought conditions that plagued Colorado in 2002 have resurfaced, and most long-term indicators point to continued drought. The good new is that there are some relatively simple changes and considerations for your landscaping to make it resilient to these conditions.
Some of the lessons we have learned and changes that can be made to your landscaping to better withstand drought include:
- Design new landscapes to be more drought tolerant in the first place. Take a more thoughtful professional approach to your landscape design and consider long term maintenance costs as well as installation costs. Consider hiring a landscape architect or design professional.
- Install the latest irrigation technologies to eliminate wasted water: smart weather based controllers, rain sensors, efficient spray nozzles and drip irrigation, to name a few.
- If lawn areas are not used for foot traffic, and are simply for aesthetics, convert these areas to masses of low growing shrubs, groundcovers, or native grass. You can achieve a similar look with plant massings at the groundplane while reducing water needs and maintenance requirements significantly.
- If you have an older irrigation system, consider having a professional do a water audit, and upgrade old nozzles to new, more efficient ones. If you are stuck with a landscape that requires a lot of water (such as large areas of bluegrass with spray irrigation) you should at least fine tune your sprinkler system. This approach is kind of like putting lipstick on a pig (since your landscape will still “require” the same amount of water to be healthy), however there are some new irrigation nozzles such as the Hunter MP Rotator that can be much more efficient at delivering water where it’s needed. At the very least, these upgrades could be a stopgap measure until the landscape can be renovated.
- Remove large areas of high water use bluegrass and lawns, and replace with native or drought tolerant plantings. A renovation of this sort will make the biggest impact by far. You can covert your landscaping from one that requires a lot of water to remain healthy, to one that requires minimal water and still looks beautiful.
So there you have it. The drought is here to stay. Colorado is a semi-arid climate that will remain dry. While tweaks and minor changes to irrigation systems can provide temporary relief, landscaping that requires a lot of water to stay healthy will always struggle in Colorado and the best approach is to install drought tolerant landscaping from the start, or renovate your landscaping to plantings that require less water.
This is the official blog of Outdoor Design Group, Colorado Landscape Architects. For more information about our business and our services, click here.
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by Matt Corrion
On March 15, 2012, facilities across the United States must comply with the revised ADA (Americans with Disabilities Act) design standards adopted in the 2010 Standards for Accessible 
Design.
The 2010 Standards set minimum requirements for newly designed and constructed or altered State or local government facilities, public accommodations, and commercial facilities to be readily accessible to and usable by individuals with disabilities.
I have reviewed the new standards, and they are pretty extensive. Property owners and designers should be aware of some of the changes that will be required when constructing or altering a facility.
The provision requiring accessible means of entry/exit for swimming pools has gained a lot of attention. On March 15th, the US Attorney General signed an extension of 60 days for this particular provision, while also opening up a public comment period.
The swimming pool provision, along with other key new provisions, as taken from the ADA website, include:
2. Recreational Boating Facilities (Sections 235, 1003)
If boat slips are provided at a boating facility, the minimum number that must be accessible depends upon the size of the facility. Accessible boat slips must be dispersed throughout the various types of boat slips.
Where boarding piers are provided at boat launch ramps, at least 5% (but no fewer than one) must be accessible. Gangways that are part of a required accessible route are to be accessible, subject to certain enumerated exceptions.
4. Fishing Piers and Platforms (Sections 237, 1005)
Newly designed, newly constructed, or altered fishing piers must provide accessible routes, subject to the same exceptions permitted for gangways. At least 25% of guardrails or handrails must be no higher than 34 inches and must be dispersed. Clear floor or ground space must be provided at each accessible railing, and turning space must be provided on the pier.
5. Golf Facilities (Sections 238, 1006)
Newly constructed and altered golf facilities must have either an accessible route or golf car passages with a minimum width of 48 inches connecting accessible elements and spaces within the boundary of the golf course. An accessible route must be provided to the golf car rental area, bag drop-off areas, and other elements that are outside the boundary of the golf course. One or two teeing grounds (depending on the total number provided) per hole must be accessible.
If weather shelters are provided, a golf car must be able to enter and exit the shelters. Certain percentages of practice teeing grounds, practice teeing stations at driving ranges, and putting greens must be accessible.
6. Miniature Golf (Sections 239, 1007)
At least fifty percent of all holes on a miniature golf course must be accessible. These accessible holes must be consecutive, and they must be on an accessible route. The last accessible hole must be on an accessible route that connects to the course entrance or exit without going back through other holes.
7. Play Areas (Sections 240, 1008)
Play areas designed, constructed, and altered for children ages two and over in a variety of settings, including parks, schools, childcare facilities, and shopping centers, are covered.
Accessible ground and elevated play components, accessible routes, ramps and transfer systems (typically a platform or transfer steps), and accessible ground surfaces must be provided.
8. Swimming Pools, Wading Pools, and Spas (Sections 242, 1009)
Accessible means of entry/exit are required for swimming pools. Such accessible means of entry include a pool lift or sloped entry, and either a transfer wall, transfer system, or pool stairs. Wading pools must provide a sloped entry, and spas must provide a pool lift, transfer wall, or transfer system. Wave action pools, leisure rivers, and sand bottom pools where user access is limited to one area shall not be required to provide more than one accessible means of entry, either a pool lift, sloped entry, or a transfer system.
This is the official blog of Outdoor Design Group, Colorado Landscape Architects. For more information about our business and our services, click here.
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by Matt Corrion
You may have heard that you can save big bucks on water and maintenance by renovating your landscaping to be more water-efficient.
But, did you know that Cities across the country will pay you cash to do it?
As water supplies dwindle and populations rise, many municipalities are offering great incentives for reducing water use in the landscape. When property owners, businesses, or managers factor in the payback from these rebates along with the water and maintenance savings, a landscape renovation can make a lot of sense.
The 2 Main Types of Rebates
Generally speaking, incentives for reducing water use fall into two categories. The first category is paying customers to remove landscapes that have high water use and replace them with attractive low water use plantings, and the second category is to provide rebates for purchasing and installing irrigation components that reduce water use and that are more efficient than older systems.
As we have discussed in the past, the real water savings (as well as the largest rebates) come from replacing high water use lawns and landscaping, with new plantings that require less water and are more adapted to the local climate. There are many benefits to this approach- see The Top 10 Benefits of Making Landscaping More Water Efficient.
14 Specific Examples of Rebate Programs
Incentives for Removing Turf: $0.75 per square foot for single family homes and multi-family or commercial properties.
Equipment Rebates: Rebates for smart controllers, rain sensors, rotary nozzles, and equipment for removing sod and placing compost.
Additional Program Notes: Rebates of up to $150.00 are also offered for rainwater collection systems, and with the installation of a rainwater collection system the incentives double to $1.50 per square foot. Residents may also receive a $20.00 credit for attending a water efficiency class.
Equipment Rebates: Rebates for smart water controllers, weather sensors, and moisture sensors for single homes and multi-family or commercial properties.
Additional Program Notes: Rebates include 50% of the purchase price for valves, and $75.00 per drip zone installed.
Incentives for Removing Turf: $1.00 per square foot, up to $10,000 for single family homes, and up to $25,000 for multi-family or commercial properties.
Additional Program Notes: Rebates are also available for removing old hardscapes, and for seeding areas with native grasses.
Incentives for Removing Turf: $18.50 per 1,000 gallons of water saved for multi-family or commercial properties.
Equipment Rebates: Single family residential customers can receive $2.00 per efficient nozzle and $100.00 for weather-based smart controllers with rain sensors. Multi-family or commercial properties can receive $2.00 per efficient nozzle, and 25% of the cost of a smart controller.
Equipment Rebates: Single family residential customers can receive up to $1,000 for installing smart controllers and rain sensors. Multi-family or commercial properties can receive up to $5,000 for installing smart controllers and rain sensors.
Additional Program Notes: Rebates are also available for rotary nozzles, mpr spray heads, pressure reducing drip valves, and backflow prevention devices specifically made for drip systems.
Incentives for Removing Turf: $0.25 per square foot for installing drought tolerant Buffalo Grass for single family homes and multi-family or commercial properties.
Equipment Rebates: Rebates of $50.00 for moisture sensors, and 50% of the purchase price of a drip irrigation system are available for single family homes and multi-family or commercial properties.
Equipment Rebates: Single family residential customers can receive up to $550.00 for installing smart controllers, rain sensors, and rotary nozzles. Multi-family or commercial properties can receive up to $3,550.00 for installing smart controllers, rain sensors, and rotary nozzles.
Additional Program Notes: Rotary nozzle rebates are available for up to $200.00 for single family residential, and up to $2,000 for multi-family or commercial properties. Rebates are available for 50% of the purchase price of smart controllers and rain sensors.
Incentives for Removing Turf: Rebates of up to $1,650 are available for single family homes and multi-family or commercial properties.
Equipment Rebates: Rebates of up to $250.00 are available for installing smart controllers.
Incentives for Removing Turf: Up to $3,000 for single family homes and multi-family or commercial properties.
Equipment Rebates: Single family residential customers can receive up to $250.00 for installing smart controllers. Multi-family or commercial properties can receive up to $1,250.00 for installing smart controllers.
Additional Program Notes: A minimum area of 1,000 square feet of turf must be removed to qualify for turf removal incentives.
Incentives for Removing Turf: $1.50 to $1.00 per square foot, up to $300,000 for single family and multi-family or commercial properties.
Equipment Rebates: 50% of the cost of smart controllers, and $25.00 for rain sensors for single family and multi-family or commercial properties.
Incentives for Removing Turf: $1.50 per square foot up to $3,000 for single family homes, and $1.50 per square foot up to $9,000 for multi-family or commercial properties.
Equipment Rebates: Single family residential customers can receive up to $400.00 for installing smart controllers. Multi-family or commercial properties can receive $25.00 per station up to 68 stations ($1,700) for installing a smart controller.
Additional Program Notes: Rebates of $0.50 for every gallon of storage capacity up to 400 gallons are offered for rainwater collection systems.
Incentives for Removing Turf: $0.75 per square foot up to $2,000 is available for for single family homes, and $0.75 per square foot up to $20,000 is available for multi-family or commercial properties.
Equipment Rebates: Rebates are available for smart controllers, rain sensors, rotary nozzles, and dedicated landscape meters.
Additional Program Notes: Rebates of $1.50 per square foot up to $30,000 are also available for commercial properties through a “cost sharing areas” program.
Equipment Rebates: Single family residential customers can receive up to $375.00 in equipment rebates. Multi-family properties can receive up to $500.00 for new equipment.
Additional Program Notes: Rain water harvesting rebates of up to $5,000 are available for no-pressurized or pressurized systems.
Incentives for Removing Turf: Rebates of up to $400.00 are available for reducing water bill for single family homes and multi-family or commercial properties.
Equipment Rebates: Rebates of up to $3,200 are available for installing smart controllers, rain sensors, and rotary nozzles.
Additional Program Notes: Incentives are offered for capping irrigation zones and/or converting existing irrigation systems to drip.
These incentive and rebate programs are typically limited to a maximum allowable rebate amount based on the area of the project, and the purchase price of the irrigation components. Many of the programs also are only available on a first come first serve basis. With limited funding many municipalities exhaust their funds in the first few months of the year. Other program requirements include selecting plants from specific drought tolerant or native plant lists, percentage of plant area coverage, and the make and model of irrigation components.
Because of the complexity of the projects and the paperwork involved, it may make sense to have a landscape architect assist you for a moderate fee. These professional consultants can prepare any plans that are needed, submit applications, gain approval from local building departments and HOA’s, and maximize the potential rebate amount you will get back.
In addition, most states require a licensed landscape architect to prepare plans for any major renovation on a commercial or larger residential property. The fees for these services are often offset by the savings that come from having a good plan that can be accurately bid and installed by contractors.
So, if you are looking to make your property more sustainable, update it’s image, and save on maintenance and water, look into what programs may be available in your area.
This is the official blog of Outdoor Design Group, Colorado Landscape Architects. For more information about our business and our services, click here.
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