Non Natives in Your Landscaping

[Chet]

I am reviewing a development's landscape plan and I'm finding an extrordinary number of plantings that are not native to our region. Would you allow this? My initial reaction is no, but perhaps with a few exceptions for ornamentals.

Any thoughts?

 

[Habanero]

I am reviewing a development's landscape plan and I'm finding an extrordinary number of plantings that are not native to our region. Would you allow this? My initial reaction is no, but perhaps with a few exceptions for ornamentals.

Any thoughts?

I don't think we'd allow a great number of them, our guildlines are to follow the Xeriscape principles. However, if they can use reclaimed water the standards for lower water demand plants and limited turf areas are not an issue.

 

[donk]

I would be more concerned over zone hardiness, snow cover requirements and soil hardiness then if the plant is a native species. Only exception is Purple Loostrife(Lythrum salicaria) don't let it anywhere near your jurisdiction if you can avoid it.(Highly invasive weed that chokes out wetlands) Goosenecked Loostrife (Lysimachia clethroidess) is OK as it is a completely different species

I had an argument with a Landscape Architect from another warmer province who did some planting plans up for a big box retailer. I told her that the plant she wanted to plant would not grow here, she insisted it would. I was forced to back down. The shrub has since been replaced with something that will grow here.

 

[Cardinal]

Generally, no. We state a preference for native plants and may even offer some suggestions. A few non-natives may not be much of an issue, but not an entire landscaping plan. If we see something listed on the planting plan that we do not like, we will tell them to replace it. For instance, I made a comment about buckthorn yesterday. We also look for some diversity in the plantings. I always encourage people to use one of the native seed mixes for detention basins (grasses, sedges and forbs), which are also designed not to be mowed. So far nobody has taken me up on this, and I can't get the public works people to realize that it is much less maintenance if they end up taking it over.

 

[SGB]

What are these landscaping plans you speak of? B-)

Only about 50% of our municipalities even have local site plan review authority, and most of those codes will basically accept any landscaping that is proposed.

Our communities are centuries away from requiring native species! :-\

 

[NHPlanner]

As usual, Chet poses a question, and my regs have an example.

3.09 LANDSCAPING DESIGN STANDARDS
a. The existing landscape of Londonderry is diverse, containing natural wooded environments, orchards and open fields, as well as wetlands and streams. New development should be respectful and sensitive to the dominant landscape character of Londonderry as a whole.
b. The purpose of landscaping design standards in Londonderry are to:
1. Preserve and enhance the character of Londonderry’s landscape
2. Enhance the goals of the Master Plan, the Zoning Ordinance, and the Orchard and Open Space Preservation Plan, and provide attractive settings for new development.
3. Preserve and enhance local and regional open space resources such as, but not limited to, the apple orchards and the Musquash Conservation Area.
4. Preserve the integrity of valuable historic resources, particularly stonewalls and dwellings and structures listed in the Heritage Commission's Cultural Resource Survey.
5. Support and encourage the use of sustainable design principles and operating practices that preserve and enhance wildlife habitats, water quality, and overall health of the natural environment.
6. Encourage the use of indigenous plant material to provide natural habitat and food sources and to maintain ecological diversity.
7. Maintain a quality image of the public spaces within Londonderry and high property values for present and future development
c. General Requirements:
1. All required landscaping shall be located entirely within the lot, unless agreements have been made with the Town for landscaping in the road right-of-way.
2. Native plants shall be used in appropriate locations, such that individual plants are selected for their ability to thrive in or adapt to the particular soil and light conditions they are placed in. (For a list of recommended native plants, see Appendix LS1: Notes on Native Trees and Shrubs and Their Use in Landscaping)
3. Under no circumstances shall any plants be used that are recognized by the horticultural or agricultural industries as invasive, whether they are native or exotic (non-native). (For a list of known invasive plants, see Appendix LS2: Notes on Native Trees and Shrubs and Their Use in Landscaping)
4. All plant material shall have a minimum winter hardiness for Zone 5B as determined by the American Standards for Nursery Stock.
5. Minimum sizes for plant material, unless indicated elsewhere in these regulations or the Zoning Ordinance, shall be as follows:
i. Deciduous shade trees: three inch caliper,
ii. Deciduous ornamental trees: two inch caliper, and
iii. Evergreen trees: six foot height.
6. Landscaping shall be laid out in informal drifts rather than formal rows and shall undulate with site topography. Individual clusters of trees or islands of shrub beds are acceptable as long as the tree clusters and/or shrub islands overlap. Linear solutions shall be avoided wherever possible, unless existing landscaping is so arranged.
7. The applicant may request that the Planning Board determine that existing vegetation is suitably located, sufficiently visually impervious, and vigorous enough to be substituted for landscaping material required by these regulations.
8. Plant material located within 20 feet of any road or other paved area shall consist of species recognized by the nursery, horticultural and botanical industries as being tolerant of roadway deicing salts.
9. Landscaping requirements for parking lots are located in Section 3.11f.
10. Landscaping shall be maintained in good condition, and any dead vegetation shall be replaced within one year.
11. No person shall deface, alter the location, of, or remove any stonewall which was made for the purpose of marking the boundary of, or borders, any road in the Town of Londonderry, except upon written consent of the Planning Board with written comments from the Heritage Commission.
12. Landscaping shall be designed so that it does not interfere with sight distances at driveways.

d. Preservation of Existing Vegetation
1. Buildings, parking, loading docks, access roads, and other site elements shall be sited to preserve existing healthy mature vegetation and maintain natural topography to the maximum extent feasible.
2. Healthy trees with a minimum 12 inch caliper, and existing wooded areas are recommended for preservation, particularly those trees located within setback areas where buildings cannot be constructed.
3. Construction activities and site alterations shall not disturb the root zone of the trees designated for preservation. During construction, the applicant shall install and maintain tree protection fencing, or other protective measures approved by the Planning Board, located 12 inches off the drip-line of the trees to be protected. All no-cut zones shall be appropriately monumented and delineated on the site plan.
4. The applicant shall be responsible to replace any trees designated to remain, which have been damaged, killed, or removed as a result of construction activities. The Planning Board requires replacement-in-kind, per caliper inch of deciduous trees and by height for evergreens. Two inch caliper deciduous trees and 4 foot tall evergreens shall be the minimum size used for replacement. For example, if a 24-inch caliper deciduous tree is damaged or killed during construction, the applicant shall replace the tree with six 4 inch caliper trees, or any other combination that adds up to 24 caliper inches. A 36-foot tall evergreen, for example shall be replaced with six 6 foot tall evergreen, or any other combination adding up to 36 feet.
e. Screening
1. Screening shall be a year-round visually impermeable barrier that may be existing, constructed, or a combination thereof.
i. Existing screens may consist of natural topographic landforms, rock outcrops, or vegetation that is dense enough to be visually impermeable.
ii. Constructed screens may consist of built screens, such as walls or fences, topographic screens, such as berms or landforms, vegetative screens consisting entirely of evergreen material, or a combination thereof.
2. Screening is required to soften the visual impact of buildings, parking areas (see Section 3.11f), loading docks, trash disposal areas, exterior storage, and other unsightly areas associated with or generated by a particular development as viewed from a public right-of-way, residential zoning districts, and the principal entrances of buildings on abutting lots.
3. The use of existing vegetation, topography, and natural features to comply with screening requirements is encouraged.
4. Screening may be required, at the discretion of the Planning Board, along the entire front setback or only a part of it. Screening may also be required to extend beyond the minimum setback areas or further into the lot, particularly if the building is located beyond the minimum setback or if the lot configuration is such that the visibility into side or rear setbacks is unimpaired from the public right-of-way, residences, and principal entrances on abutting lots.
5. A minimum of 50% of built screens which face the public right-of-way, residences, and principal entrances on abutting lots shall be softened with landscaping.
6. Vegetative screens shall achieve a minimum of 75% vertical opacity to a height of 6 feet, year-round, within one year of installation. Screens shall not be located so as to impede vehicular or pedestrian traffic.
f. Maintenance
1. The owner of any lot shall be responsible for the maintenance of all landscaped open space, natural screens, and constructed screens within the lot. Landscaping shall be maintained in good condition such that planting shall be vigorous and in good health at all times and that the parcel shall present a healthy, neat, and orderly appearance, free from refuse and debris. Any dead vegetation that is part of the approved landscaping design shall be replaced within one year.
2. Landscaping shall be maintained so that it does not interfere with sight distances at driveways.
3. The Planning Board, at its discretion, may require a landscape maintenance and water management plan. The maintenance plan shall include, but not be limited to the following:
i. Integrated Turf Management: mowing schedule, weed control, pest control, soil pH management, fertilizer plan, aeration/dethatching schedule, repair/replacement plan.
ii. Shrub and Groundcover Management: mulch schedule, weed control, pruning where needed for visibility, preventative pest/disease management, repair/replacement plan.
iii. Tree Management: mulch schedule, weed control, deadwood removal, pruning schedule, particularly for trees located next to walkways or roadways, fertilizing schedule, preventative pest/disease management, repair/replacement plan.
iv. Water Systems Management: water source, system description, spring start-up, fall close-out, system testing schedule, repair/replacement plan. The applicant may install a permanent water supply system consisting of a sprinkler system and/or hose bibs placed at appropriate locations and intervals. Wherever possible, irrigation water shall be derived from sources other than the municipal water system, including “gray water,” re-used water, detained stormwater, roof drainage, or water from on-site wells. “Gray water” is water from sinks, showers, dishwashers, and washing machines. On-site cisterns may be installed to store water for irrigation.
v. Rodent Control: design preventative measures, operational preventative measures, monitoring, schedule, remediative action plan.
vi. Seasonal Maintenance: Spring clean-up plan, fall clean-up plan, disposal plans for leaves and plant debris, winter plowing plan, winter deicing plan.

For the Appendices, go to http://www.londonderry.org/images/siteregs2002b.pdf and see pages 69-71.

 

[Michele Zone]

Our communities are centuries away from requiring native species! :-\

Well, clearly, whatever is being planted now will BE the "native species" of the area by the time they start regulating such things! :-0

 

[Repo Man]

We woudn't allow non-native species to dominate a landscape plan, however in some cases we have actually used non-native species for streetscape projects because they stand up to the salt and other strains put on them better than some native species.

 

[boiker]

Non-native species are allowed, but policy encourages a plan dominated by native species.

We have this policy to allow evergreens to be planted for screening purposes, which are not native to central illinois.(to my knowledge)

 

[Habanero]

OFF TOPIC:

I don't want your non natives in my landscaping! 8-!

 

[Cardinal]

Non-native species are allowed, but policy encourages a plan dominated by native species.

We have this policy to allow evergreens to be planted for screening purposes, which are not native to central illinois.(to my knowledge)

The shortleaf pine (Pinus echinata)'s territory goes north to the southern part of Illnoise but probably stops well before you. White pine (Pinus strobus) comes in from the north and there are outlying stands into northern Illnoise. Red cedar (Juniperus virginiana) is more likely to be found in the central part of the state, as is the ubiquitous arborvitae (Thuja occidentalis). I am not a purist, though, and have no qualms about using a tree native to the U.S. beyond its native range. I have planted yellowwood, tulip poplar, sycamore, and other trees more likely to be found 100-200 miles south of here. This is still preferable to Asian or European species. Unless you are doing a restoration project there is no need to stick to those plants only found in the immediate area.

 

[Lee Nellis]

It depends on the landscape you're working in, but as others have suggested there may be applications, particularly in formal or semi-formal spaces where there will be a lot of traffic, where use of a non-native is reasonable.

 

[The Irish One]

A nonprofessional opinion/ observation

Generally speaking in San Diego all native vegetation is replaced with subtropicals from all over the world, not to mention Scotland's finest sod. A developer might actually get busted for planting natives for reasons of fire and aesthetic value. I can't really back the aesthetic claim but the current state of landscaping would leave no doubt that a certain subtropical look is the acceptable norm. I'd be shocked if it wasn't the code enforced preference (I really don't know). I frequently look for native landscapes and find very few. I've worked for a nursery that is exclusive to California native's and business isn't booming. Go to the local subtropical variety nursurey and things are fine. I'm shocked and pleased to hear any responses that enforce native vegetation.

Rant
Enforcing any laws requiring native vegetation for business or, god forbid, housing, would be way to communist for this county. People here want to use as much water as possible. In the winter one can see the frost burnt leaves of all the palm trees and in the summer it's the green lush grass that dies off despite constant watering. It's funny (sort of) that the silent minority of people who want a more responsible landscape are taxed by the vast majority who unknowingly assume we have the water supply of Rio de Janeiro, Brazil . Don't get me wrong I want kids to have grass to play on etc.. and I'm grateful and awe struck by the incredible infrastructure that makes this possible. Our resevoirs are at all time lows.There is a responsible limit to nonnative species.

 

[Michele Zone]

Rant
Enforcing any laws requiring native vegetation for business or, god forbid, housing, would be way to communist for this county. People here want to use as much water as possible. In the winter one can see the frost burnt leaves of all the palm trees and in the summer it's the green lush grass that dies off despite constant watering. It's funny (sort of) that the silent minority of people who want a more responsible landscape are taxed by the vast majority who unknowingly assume we have the water supply of Rio de Janeiro, Brazil . Don't get me wrong I want kids to have grass to play on etc.. and I'm grateful and awe struck by the incredible infrastructure that makes this possible. Our resevoirs are at all time lows.There is a responsible limit to nonnative species.

When I lived on Ft. Irwin, in the bleeping Mojave Desert, just South of Death Valley, we were REQUIRED to have grass in the backyard. The grass regularly died. I can't remember the name of it, but there was an agency on base where you could do things like check out a lawnmower for 3 days and they also provided grass seed (I think). It didn't really "cost" us anything but time and effort, since you also do not pay utilities (like water) when you live on base. But it so galled me. The kicker: we had to remove the cacti I had planted in the flower beds when we were leaving so no child could get hurt when new people moved in.

 

[H]

While growing up in ATL I had many ‘non-natives’ in my landscaping and it really detracted from the aesthetics. Nothing was done about the problem and now the environment has completely changed and is overgrown with the evasive take over and the native species have been driven out. Through a complicated scientific experiment, I am now able to see through the eyes of a non-native living in the state of Florida.

Here most environmentalist and landscape architects are h#ll bent on removing non-native plant species, which brings us to my new proposed slogan for the state:

“FLORIDA: where the plants are native, but the people aren’t!” :-D

(Except of course for the beloved ZG)

 

[B'lieve]

Non-planner/budding biology teacher's perspective:
The main problem with (some) non-native species is that they can be invasive, readily spreading to the wild and, unchecked by predators or other natural controls, crowding out native species. Some even become agricultural pests. I would come up with a list of invasive species that either are known to grow in the area or are commonly planted in or native to a similar climate/soils and have proven elsewhere to be invasive. Those are the ones that should be restricted or banned. That makes more sense to me than a blanket restriction or ban, and would probably stand up better to any public complaint or legal challenge.

A good place to start researching such a list would be InvasiveSpecies.gov, which profiles some of the most common problem weeds and critters, and has links to related resources.

 

[boilerplater]

Hear, hear

I'd like to second B'lieve's point about restricting the invasive species, the ones that do real harm to ecosystems. That problem needs more resources devoted to it, more public awareness, etc. The biological diversity of so many ecosystems is being reduced due to invasive plants. Making a blanket regulation of no non-natives would prohibit a lot of useful plants that actually do better than natives in a lot of the man-made situations in urban environments. For example, many of the sedums that are typically used in extensive green roofs are not native. You don't want to prohibit green roofs, do you? Also, there is considerable debate in the horticultural community about when a plant can truly be considered "native" Many of our ornamental species in the northeast are exotic and have been in cultivation since the 17th century with no ill effects. And what about plants that once grew in a region but have become extinct? Where do you draw the line?

By the way, that Londonderry, NH reg is one of the best I've seen for having qualitative descriptions that actually may enhance local character rather than trying to be like some other town.

 

[Chet]

By the way, that Londonderry, NH reg is one of the best I've seen for having qualitative descriptions that actually may enhance local character rather than trying to be like some other town.

yeah, but it was waaaaay too much for most communities around here to bear -- HNP, what ever happened to the "Live Free or Die" mantra!

 

[The Irish One]

Also, there is considerable debate in the horticultural community about when a plant can truly be considered "native" Many of our ornamental species in the northeast are exotic and have been in cultivation since the 17th century with no ill effects.

I think the term used in these parts is naturalized for invasive species that have a new permanent home. California has a lot of native mustards, but the one mustard that you'll encounter most often is the invader from Europe or Asia Minor ??(not sure of its origin).

 

[NHPlanner]

yeah, but it was waaaaay too much for most communities around here to bear -- HNP, what ever happened to the "Live Free or Die" mantra!

We like our development high quality 'round here.