they’re cute when they’re little!

Answering another question with yet another question:  How much biotic activity is there in a loam pile, over six feet in height, that has been sitting for more than 24 hours on a site?  My understanding is that compost must be stored in windrows of no higher than six feet to avoid creating an anaerobic (and thus life-inhibiting) condition for organisms in the compost; is soil any different?  And if it isn’t, is there value in hanging on to a site’s native soil once that soil has been stored in piles too high to sustain life?  The storage of soil components probably must be addressed in the soil spec.

Just one of those thoughts that wakes me up at night…

We have a string of comments going on Toby’s sedum post, and now I’m going to add another question to the mix:  is there evidence that sedum won’t escape from rooftops and become invasive in places where it may be unwelcome?  It’s being used so heavily in green roof construction, and being pitched as a really great plant for these harsh places.

How is it done?  What kind of equipment is used?  What does it take to assure a consistent blend?

Two advantages of green roofs are their ability to cool the building below and the air above, and to reduce stormwater runoff volumes, thanks to the transpiration of moisture through their leaves.  The most common green roof plant are species of Sedum.  Those plant can survive drought conditions in the rooftop environment in part because they transpire relatively little water through their leaves.

To what extent does the characteristic that helps Sedums survive, their low transpiration rate, negate their environmental benefits?  Is the performance of a Sedum-planted roof significantly higher than that of a non-planted roof with the same construction and soils?  If not, does the Sedum offer other benefits that still make its use worthwhile?  If it offers no real benefits, and a higher-benefit roof is not feasible, is the only alternative a conventional roof, or is a plant-free soil-covered roof a realistic alternative?*

*Green roof people discourage the use of the word soil in favor of “growing medium.”  In a world of where manufactured soils are more and more the norm for built landscapes, I am not sure there is a meaningful distinction.

In the Euonymus post, I was mostly interested in the pattern of fallen leaves on the stone (geometric meets organic again), but the shrub seemed necessary to complete the story.  In these two photos, I was ok with leaving out the source of the leaves.  Maybe because the Japanese Maple leaves are so recognizable and beautiful in themselves, or maybe because I couldn’t find a way to include the tree, or maybe because I was shooting patterns more than things, or maybe because the fallen leaves in these are impossible to miss.  In any case, the simple narrative (that leaves fall) is a more important part of the image than I would have expected.

Check out the landscape photography of Lyle Gomes.

Scanning back over Toby’s recent photos, it’s clear to me that each one is more compelling for seeing the interplay of ordered form versus organic form.  The mausoleum’s stepped wall sets off the scatter of euonymus leaves; the billowing trees in Central Park provides a foil for oh-so-formal pool and fountain.  You get to choose:  do you prefer resting your eyes on the natural?  That pool heightens its naturalness.  Are you more comfortable with the manmade?  The foliage, the tree forms, the irregular edges all set off the ‘knowness’ of masonry and compass arc.

. . . and its friends