Turf in Public Parks – a note

The upper portion of Duniway Park.  A Nyssa sylvatica growing at the toe of the slope below OHSU.  The turf is completely unirrigated, is very compacted and has poor drainage.  In much of it is dominated by a few broad leaf weeds while most of the grasses that survive are weedy as well.  The whole Park is built over one of Portland's first dumps.

The upper portion of Duniway Park. A Nyssa sylvatica growing at the toe of the slope below OHSU. The turf is completely unirrigated, is very compacted and has poor drainage. Much of this turf is dominated by a few broad leaf weeds while most of the grasses that survive are weedy as well. The whole Park is built over one of Portland’s first dumps.

I wrote what follows a couple of years ago while still a horticulturist with Portland Parks and Recreation.  It was an addendum to a piece I wrote addressing a different approach for prioritizing work in Park landscapes and is reproduced here, with slight changes, as i originally wrote it.  I thought of it more recently as I’ve watched Portland bake this summer and observed, consequently, the decline of residential and Parks lawns. I am a big proponent of ‘sustainable’ landscapes.  That does not prevent me from seeing the necessity for grass lawns in urban areas especially in cities as they follow the path to increased density for sustainability issues as well.  People ‘need’ open space and as we all ‘suffer’ from our own shrinking of private outdoor space, the need for such public spaces increases.  But turf cannot fill the need if it is poorly maintained.  Dormant, dry, compacted weed dominated lawns are both unattractive and less functional.  Open spaces are not all the same.  Ugliness can degrade them to the point of rendering them almost useless in terms of their human value (We often speak of habitat value for wildlife and in terms of water quality.  We spend less public time discussing what is of basic human value.  What we require to meet our very real and ‘animal’ needs.  Not all of our legitimate needs can be met by buying products and services.)

Vigorous grass based turf is not sustainable. It is a monoculture susceptible to weed invasion that requires regular care, including, irrigation, mowing, fertilization, aeration to reduce compaction, occasional dethatching, control of moles and, for the best stands, the occasional well timed application of an herbicide and insecticide. Having said this, I still see it as a vital component of our Parks.  Portland Parks and Recreation has other priorities making exceptions Park by Park, though select athletic fields for playability and safety reasons are still irrigated. (Other Parks Districts, notably places like Bend, OR, with a desert environment, have prioritized having good quality turf in public areas). No other surface provides the functionality and value of turf grass in an urban environment. It absorbs rainfall; reduces the problems of mud and dust and helps control the erosion that accompanies bare soil; provides a firm, but shock absorbing surface for activities; aids with cooling the urban heat island; provides a restful carpet of green that helps calm a potentially chaotic visual world; and, provides a surface for young children to play on or family and friends to relax or picnic on. As urban density increases, the need for public open space increases. We need lawn. Concrete, pavers and asphalt will never fill all of this need. An argument can easily be made that rich healthy lawns better fill this human need when they are in Parks than scattered thinly through residential neighborhoods in front and backyards where they are individually too small or inaccessible to meet the public need.

We need to understand that useful healthy turf cannot withstand the pressures that dense urban life places on it without a commitment to maintain it. Dry, poorly maintained turf will quickly degrade into weedy patchiness. As such, it loses most of its value, even leaving it limited function as a permeable surface, if it is too compacted from foot traffic. Such lawns serve as a continuous weed seed bank that infect our adjacent planted bed areas, which then require the use of herbicide and/ or labor we no longer have.

Tom McCall Waterfront Park north of the Morrison Bridge looking toward the Battleship Oregon's Mast.  This shot was taken mid-way through the summer's event schedule.  Park's makes a herculean effort to keep this Park up.  Much expense is taken, but it simply gets trampled down to bare soil regularly.  It is nursed back and then trampled again repeatedly by scheduled events.  One use of this area is by children from area day care centers who will often dig in the exposed soft sand.

Tom McCall Waterfront Park north of the Morrison Bridge looking toward the Battleship Oregon’s Mast. This shot was taken mid-way through the summer’s event schedule. Park’s makes a herculean effort to keep this Park up. Much expense is taken, but it simply gets trampled down to bare soil regularly. It is nursed back and then trampled again repeatedly by scheduled events. One use of this area is by children from area day care centers who will often dig in the exposed soft sand.  Where grass does grow it is often dominated by Annual Blue Grass which is tolerant of compaction but is not very tolerant of heavy foot traffic.

Healthy managed turf requires less herbicide than lawns that receive little care other than mowing and no to minimal irrigation (unless we chose to completely abandon them). Stressing turf by droughting it out degrades the health of the desired grasses giving an advantage to weeds that are by definition more competitive.  Healthy lawns, especially those subject to the heavy use that public areas get, require a commitment to maintain them, and the recognition, that they serve an invaluable function in urban society. Over the years, due to budget cuts and public pressure to reduce chemical use, save the salmon, etc. we have simply stopped doing what was once common practice. We have cut irrigation, in many situations to nothing, we have over scheduled events and sport activities not allowing turf time to recover, we have stopped fertilizing, aerating and/or de-thatching. Even the pressure from dog use, their habit of spotting with urine and defecation leads to lower quality turf requiring regular action on our part (Some would argue that the protected status of Geese in some Parks should be questioned for the same reasons.) These things have allowed the growing conditions for the grass to deteriorate. In most cases now, the existing conditions actually favor the growth of weeds. Now, by not spraying at all, there is nothing to keep the weeds from dominating absolutely. We cannot expect ‘nature’ to step in and grow healthy vigorous turf for us. Grass lawns are an ‘un-natural’ landscape. Grass lawns in Parks are routinely subject to pressures that no natural surface can tolerate unaided. We have a decision we need to re-think and make consciously. We have allowed others to target lawns as detrimental to the environment and of little value to society. And, so we have allowed them to become just that.

Grass turf does in fact possess human value.  If we look at our degraded turf today as an indicator of public use it will not give us an accurate picture.  Degraded turf is less functional and ‘ugly’.  People will search out alternatives.  They will cling to their own private lawns.  Residents cannot get all of their outdoor needs met relaxing on their increasingly tiny balconies, their vanishing backyards and degraded public open spaces.  Portland needs quality turf and it is better to have it professionally maintained than it is in a patchwork of isolated, inaccessible private lawns…no matter how perfect.

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