Even with aid efforts expanded, Tower Grove's plants are suffering
The following is from a letter written about the conditions in Tower Grove Park.
I had originally expected this drought to have ended by this time, and that it would then be timely to provide a summary report. The drought has in fact not ended, and we don’t know when it will, but the temperatures have cooled off, at least for now. Accordingly, we want to bring you up to date, with the understanding that this ongoing event is still in progress, that we are only just now entering the annual normal dry period, and that when it will end is unknown to us at this time.
No one here can recall a drought as severe as the current affliction. We have not had significant rainfall since May. Even those showers that have brought mild temporary relief to other areas in our general region have tended to pass over or only lightly sprinkle the park. Wednesday night was a good example — good rain apparently at the airport, barely measurable here. Since July 1 there has been a total of less than ¾ inches of rain as measured on the park gauge.
In response, the park has mobilized, and with escalating intensity. In the earlier phases in June, we initiated our "normal" dry period strategy, shifting some mowing labor to watering duty and activating all three of our water wagons.
In a normal dry season, we use a series of resources: We have approximately 16 spigots through the park, and can attach hoses to these to cover surrounding areas, mostly near flower beds and selected entrances; we have three water wagons, each of which dispenses 400 gallons of water (this "fleet" was enlarged from two to three in 2009); finally, in recent years, we have specifically included irrigation systems in new landscaping projects, so that Flag Circle and the Lily Pond area are covered by those systems. In most years, this system works reasonably well. This has not been a normal year.
Signs of distress
As the dry weeks continued, we extended the hours of all three modes by rescheduling shifts of two sets of field staff so that the systems are working from 6:30 a.m. to 6 p.m. As it stayed bone dry and then got hotter and hotter, to save trees, we accessed funds from reforestation to further extend watering hours through the weekends with overtime. We have generally prioritized trees over turf, since recovery time and replacement costs of woody plants tends to be significantly greater.
Punishing conditions persisted. We began to note small shrub and young trees succumbing, leaves withering and turning brown, sometimes including trees that had been watered. Some species can apparently wilt from the extraordinary heat, even if kept moist. Test holes revealed that wherever irrigation did not extend, available moisture was being sucked completely out of the soil layer in which our plants live — the dirt has become like a dry powder all the way down to the clay pan.
In the course of what has evolved into a major struggle, the staff has engineered new tactical approaches: new and longer hose extensions, new hook ups with fire hydrants, and new sprinklers. One innovation has been to experiment with leaving sprinklers on and hoses out to run overnight. Our previous presumptions of theft and vandalism have so far been unrealized — very little loss or damage has occurred. Through such efforts, we have extended our potential "reach" from about 10 percent of the park to as much as 20 percent. This has made a difference.
Nevertheless, as the drought has advanced, it has become less and less possible to "cover the bases"; watering in one area only seems to reveal a worse problem somewhere else, following in a depressing downward cycle that can now only be terminated by extensive drenching rains. None is currently predicted.
With the record temperatures, the rate of desiccation also increased, and so has the health risks to the staff. I am pleased to report that our workers have risen to the occasion. They clearly understand that the park is facing a crisis, and they have responded with energy, ingenuity and determination, despite the often very stressful conditions. Of course we have provided water and extra breaks; so far no heat related illnesses have occurred. Part of the stress is emotional; it is very difficult to watch the plantings you have worked so hard to establish wither and die. I must admit to this kind of distress myself.
Out of our collection of 7,600 trees and 2,300 shrubs, significant numbers of shrubs, young trees, and some larger trees have died, several hundred at least. More will die; depending upon when real rain arrives. Some species are more vulnerable than others and we are recording variable drought tolerances for future reference. In fact, for more than a decade we had already been favoring more drought tolerant species for new plantings, and we assume that this has helped our survival rate now, at least to some degree.
But the drought is not over and we will only know the final casualty count sometime after that happens. No tree can survive indefinitely with no moisture, and right now that is essentially what most of them have.
I should add that despite the drought crisis, the life of the park does go on. The heat has some affect on attendance, but as can been seen in our staff meeting reports, scheduled events have gone forward; people do still come to the park as a refuge from the depressive effects of this summer’s historically unprecedented weather.