Picking Up the Pieces

On early Sunday morning I awoke to the sound of heavy rain beating down on my bedroom skylight.  Still half-asleep, I remembered that it was “Hurricane Day” – the day when Hurricane Irene was predicted to make landfall in New York.  For the first time in over 25 years, NY was going to experience a direct hit, and everyone was scrambling around in hurricane-mode.  The news and weather service had implored everyone days earlier to make necessary preparations and abide by mandatory evacuations – evacuations that affected 370,000 people in NYC and many more on Long Island.  Our place was not in any of the flood-prone areas, so thankfully we were able to stay.  But that didn’t mean we were immune from damage, so in the days prior, we too made our preparations, getting everything off our back deck, making sure we had flashlights and candles, and lowering the temperature of our fridge so that food would be less likely to spoil in the event of a power outage.

Photo: Our Japanese Zelkova lost only dead limbs and some leaves during the storm, Commack

So with much hesitation, build-up, and excitement, I got out of bed Sunday morning and cautiously peered out the rain-splattered window.  Outside, I saw Irene - an impenetrable layer of dark gray clouds from which rain poured down ferociously.  Her winds swept the limbs of our mature White Pines upwards in great gusts and made them look like they were dancing Christmas trees.  I looked out at our Japanese Zelkova and watched its branches move about its trunk in strange oscillations.  “Eh, not so bad out,” I thought to myself and went back to sleep, glad that the cataclysmic, doomsday scenario that was building inside my mind had not come true.            

In the days after Irene, I learned bits and pieces of information about the hurricane’s impact, and I also learned how cut-off from the world I felt with no electricity for 52 hours! (Good thing we had those candles!)  But I cannot complain when half a fridge full of groceries was our biggest loss.  As I drove around Long Island, I realized that many others were not so fortunate.  In Garden City where my parents live, breath-taking oaks that had stood the test of time, were lying in ruins across streets, cars, and houses.  In only a five block area, I counted at least 10 mature oak trees down.  My parents’ house was spared, but many of the neighbors I grew-up with were not as lucky.  70 ft. tall trees that I had walked past in elementary school fell over as easily as toothpicks, leaving a wake of destruction.  The town arborists were working round the clock to get the streets clear.

Photo: A mature, healthy Pin Oak crushes home and car, Garden City

I stared at a house a few homes down from my parents’ that was crushed by what had been an enormous Pin Oak (Quercus palustris).  The roof was caved in and branches and leaves were now part of their living room décor.  Somehow the tree had also managed to crush their car.  “Why did this tree fall?” I wondered to myself.  Trees that are unhealthy and have root or trunk decay are pre-disposed to failure during high-wind events.  But this tree was healthy and had no decay.  Trees that endure root severance from recent construction or sidewalk replacement are also pre-disposed to failure.  But this sidewalk was maybe 15 years old and no construction had taken place.  “It must be that the root system was uneven,” I thought, since there were more roots in the lawn area than under the concrete.  But then I looked down the block and saw another toppled Pin Oak that had had a vast area for its roots to grow.  Why did so many trees fall for what seems like no good reason?? 

Photo: More oaks windthrown by Hurricane Irene, Garden City

According to the National Weather Service, 4 inches of rain fell on Sunday in Central Park and the highest wind gust speed recorded at LaGuardia airport was 67 mph.  Typically lasting for about 20 to 40 seconds, wind gusts create a complex sway motion in the branches of a tree as the limbs move out of step with one another.  This movement helps prevent the tree from developing a dangerously large, pendulum-like sway.  But if the branch movement does not use up or dissipate enough energy, the energy can be transferred to the main trunk which if a sufficient force can topple the tree (James, K. 2003. Journal of Arboriculture 29(3)).  Saturated soils and high winds from Irene were simply too much for some of our trees to endure. 

Photo: Trees that have structural defects like this root girdled Red Oak (Quercus rubra) are pre-disposed to failure during high wind events, Garden City

Researchers have found that some tree species are more adapted to withstand hurricane-force winds than others.  After studying urban trees that survived devastating hurricanes in Florida, it was found that certain qualities made some trees more wind-resistant.  Losing leaves during the hurricane meant higher survival; native trees showed better survival than non-natives in some studies; tree species with a higher wood density had a higher survival rate; and surprisingly, decurrent trees with a spreading branch habit had significantly higher survival compared with excurrent trees with an upright, single straight trunk habit (Duryea et al. 2007. Arboriculture and Urban Forestry 33(2)).  This type of excurrent branch habit combined with saturated soils and high winds may have led to the Pin Oaks’ downfall.

Although the climate and soils are obviously very different in Florida, a list of Wind-Resistant Trees compiled by Florida researchers may prove to be useful here.  When re-planting your fallen trees, consider planting trees with the highest or medium-high wind resistance and avoid planting trees with medium-low or lowest wind resistance. (From Urban Forest Hurricane Recovery Program series, Chapter 5 – Wind and Trees: Lessons Learned from Hurricanes, by Duryea and Kampf).  For more information, visit The University of Florida’s Trees and Hurricanes webpage at: http://hort.ifas.ufl.edu/treesandhurricanes/index.shtml

Tree Species with the Highest or Medium-High Wind Resistance (NOTE: tree species that only grow in the north were not included in the study)

Acer palmatum, Japanese maple

Betula nigra, river birch

Carpinus caroliniana, ironwood

Carya glabra, pignut hickory

Carya tomentosa, mockemut hickory

Cercis canadensis, red bud

Chionanthus virginicus, fringe tree

Cornus florida, dogwood

Diospyros virginiana, common persimmon

Ilex glabra, inkberry

Ilex opaca, American holly

Lagerstroemia indica, crape myrtle

Liquidambar styraciflua, sweetgum

Magnolia grandiflora, southern magnolia

Magnolia virginiana, sweetbay magnolia

Magnolia x soulangiana, saucer magnolia

Nyssa sylvatica, black tupelo

Ostrya virginiana, American hophombeam

Quercus shumardii, Shumard oak

Quercus stellata, post oak

Taxodium distichum, baldcypress

Tree Species with the Lowest or Medium-Low Wind Resistance

Acer negundo, boxelder

Acer rubrum, red maple

Acer saccharinum, silver mapple

Celtis laevigata, sugarberry

Celtis occidentalis, hackberry

Fraxinus pennsylvanica, green ash

Morus rubra, red mulberry

Platanus occidentalis, sycamore

Prunus serotina, black cherry

Quercus alba, white oak

Quercus phellos, willow oak

Salix x sepulcralis, weeping willow

Ulmus americana, American elm

Planting for the Future

I don’t know much about politics.  In fact, I try to avoid the subject completely.  Yet recently, my staunch avoidance of the topic has proven to be quite difficult.  As the economy remains at a standstill, I feel like I’m being bombarded with everyone’s own personal agenda and “quick fix” solution to get our local, state, and federal governments back up to speed.  Even my daily perusal of Facebook’s news feed has taken a turn for the worse, as my “friends” keep posting things like, “CALL YOUR LEGISLATORS NOW!!! OR ELSE!!!!!!”  Personally, I don’t really care whether there’s a big or small government, so long as it works.  And unfortunately, things aren’t working quite optimally right now, to say the least.  Three years after the Lehman Brothers collapse, our nation is still in the throes of a great depression.

Currently, I’m in the middle of reading The Nature of New York – An Environmental History of the Empire State by David Stradling.  (Yes, I acknowledge that I am an incurable dork, so please hold the comments and eye rolls!)  Half a chapter of this book is dedicated to Franklin Delano Roosevelt, the President who got our country out of the first Great Depression.  Like his cousin Teddy, FDR had a deep respect for nature and strongly promoted environmental conservation efforts throughout his career in public office.  However, unlike the romantic environmentalists of the 1800s who focused almost solely on the beauty and sanctity of nature, FDR recognized the economic benefits of conserving the nation’s soils and forests.    

Photo: Many of the trees planted during the conservation era were conifers, including pine and spruce.

Roosevelt authorized the planting of millions of trees, and would have given Johnny Appleseed a run for his money.  Just on his own property in Hyde Park, NY, Roosevelt oversaw the planting of more than half a million trees.  While governor of NY, FDR advocated that scientific forestry could help improve rural economies and rural lands.  On idle upstate farmland, where soil had become depleted and unsuitable for crops, Roosevelt encouraged the planting of trees which could improve the soil and be used for timber years later.  In 1931, just two years after the stock market crash, New York’s state nurseries grew and distributed over 40 million trees.  That same year, Roosevelt expanded New York State’s reforestation program with the passage of the Hewitt Act.  This act approved state spending of $20 million to purchase abandoned land and replant with trees over the course of eleven years.  Roosevelt’s conservation policy would, in his words, “not only preserve the existing forests but create new ones.”  Hundreds of thousands of acres of abandoned farmland was purchased by New York State from failing farmers and was planted with millions of trees. 

The success of Roosevelt’s conservation programs reached across the nation when he assumed the presidency.  As part of his first hundred days in office, he proposed the creation of the Civilian Conservation Corps.  Over the course of its nine years of existence, the CCC hired up to 350,000 unemployed men at one time who planted trees, created campgrounds, constructed hiking and ski trails, built dams and reworked streams for improved fishing, and completed other public works projects across the country.  The CCE was one of the most popular components of the New Deal, providing immediate relief for the 25% unemployment rate and long-term benefits for the environment.  Other organizations such as the Civil Works Administration and the Works Progress Administration also hired men for a variety of projects in natural areas.  Today, many of these trees and public projects still stand, providing testimony to the success of Roosevelt’s conservation programs.    

Photo: Today, organizations like the Nevada Conservation Corps and AmeriCorps carry-out valuable conservation work, including trail building.

In the 1930s, Franklin Delano Roosevelt believed that planting trees could help solve the economic problems of the Great Depression, by helping to alleviate the 25% unemployment rate.  Today, at less than 10% unemployment, we are apparently in a better situation, but there are many people out there who are searching and searching and cannot find work.  Perhaps a new Civilian Conservation Corps is needed.  So CALL YOUR LEGISLATORS NOW!!! AND TELL THEM PLANTING TREES WILL SAVE OUR ECONOMY!! OR ELSE!!!!!!  Hahaha.  All kidding aside, we need to seriously begin both planning and planting for our future.

Photo: Recently planted trees at an urban park.

Tools for the Plant Doctor

Like any medical doctor, a plant doctor needs the proper tools, equipment, and reference materials to make accurate diagnoses of sick patients or plants.  As a person who lives by the motto “Be prepared,” I always make sure to bring with me all the tools I may need whenever I get a call to come check out a tree or other plant that is not doing well.  Thankfully, my vehicle is roomy enough for me and all my tools, as it has become my portable storage shed.   

Photo: Many times decay in trees is not as obvious as this large cavity in a European Linden (Tilia x europea) and special tools are required for assessment.

The most important equipment for diagnosing plant problems is perhaps the simplest – a gallon size plastic bag and some hand pruners.  With the hand pruners I can cut off an afflicted branch and store it in the plastic bag until I get back to our lab.  Plastic bags are better than paper bags because they keep in moisture and prevent samples from drying out too quickly.  Whenever I take a sample of a diseased or infested branch, I always make sure to obtain the symptomatic area, the healthy area, and the area in-between.  This “transition zone” from unhealthy to healthy tissue is often the most helpful for making accurate plant diagnoses.  If I can’t get my sample to the lab asap, I’ll store it in the fridge to prevent saprophytic decay fungi from decomposing it.  To date, I haven’t put a plant sample in my salad bowl, but I have to be extra careful when I’m hungry and tired!

Other tools that are important for taking samples are a pole pruner for cutting limbs that are out of reach, and a hand saw for removing afflicted branches that are too large for hand pruners.  I never go without my camera and always take lots of pictures to remind me of things later and to include in the diagnostic report.  A notepad and pen are essential.  I also like to bring some diameter tape for measuring the girth of trees.  I do carry around glass insect vials, but rarely get the chance to actually capture any offending insects.  A hand lens is useful for magnifying things in the field, but a microscope back at the lab is essential.  I remember once scrutinizing a California Privet (Ligustrum ovalifolium) shoot that was displaying symptoms of privet rust mite.  I squinted through my contact lenses at the curled, misshapen leaves, and after not seeing anything, I assumed that the mites had done their damage and left.   Just for kicks, I threw the shoot under the microscope, and lo and behold! there was an entire microscopic world scrambling all over the leaves, privet rust mites included!  I then promptly wondered what invisible little buggers were scrambling all over me!

Photo: California privet displaying symptoms of infestation by privet rust mite - curled, distorted, stunted, and yellowed new growth.

Other important tools for the tree doctor are a hammer and chisel for extracting wood from cankers and a pocket knife for looking beneath thin bark of branches.  As for trying to figure out how decayed a tree is, some highly specialized (and expensive) equipment has been developed.  One technique is to use a Resistograph®.  This microdrill takes advantage of the fact that decayed wood has lost strength and has a lower resistance to drill penetration than sound wood.  A graph that looks like an EKG is produced, and is great for impressing tech-oriented people and plant geeks alike.  Sounding with a mallet and using an increment borer or battery –operated drill are some less expensive methods of detecting decay in living trees.  A long rod is a cheap and easy way of probing into tree cavities to see how large they are.   

In addition to inspecting the leaves, branches, and trunk, it is absolutely critical to assess the belowground portion of a plant.  Frequently, the root cause of a plant problem is just that – the roots.  My most important tool here is a small, three-pronged hoe that I use to pull away soil and mulch from where the trunk meets the ground and examine this area known as the root collar.  I check for circling roots that can girdle the tree or shrub and to see if it is planted too deeply.  An air excavation tool can also be used to remove soil without injuring roots.  Another common belowground problem is soil compaction which means that sufficient water and air are not getting to the root system.  I use a penetrometer, a long pointed rod with a gauge at one end of it, to give me a qualitative assessment of soil compaction.  At new houses or recently re-modeled houses, my penetrometer always displays a red reading, indicating that the soil is too compacted for roots to grow.  A more quantitative assessment of soil compaction would be to take a bulk density test.  I also always bring a soil probe or hand shovel and bags for taking soil samples to measure nutrient levels and soil pH.

Photo: Soil compaction of this recently completed parking lot is the root cause of poor soil drainage and thinning of these Inkberry Hollies (Ilex glabra).

My other essential tools are the resources I can turn to when I need further information to make an accurate diagnosis.  There are a lot of books out there, but the ones that I find the most helpful are listed below.  Talking with colleagues and getting a second or third opinion also helps proper diagnosis.  Our local Cooperative Extension office has staff to help both professional horticulturists and homeowners diagnose plant problems.  Call CCE-Suffolk at 631-727-4126 and CCE-Nassau at 516-292-7990.  With the right tools and a lot of practice and patience, you’ll be a pro at diagnosing plant problems!

 
Books to Aid Plant Diagnosis:

• Costello, L.R., E.J. Perry, N.P. Matheny, J.M. Henry, P.M. Geisel. 2003. Abiotic Disorders of Landscape Plants: A Diagnostic Guide.  Oakland, CA, University of California, Publication 3420.

• Dirr, M.A. 2009. Manual of Woody Landscape Plants: Their Identification, Ornamental Characteristics, Culture, Propagation and Use, 6th Edition. Champaign, IL, Stipes Publishing.

• Johnson, W.T. and H.H. Lyon. 1991. Insects That Feed on Trees and Shrubs, 2nd Edition. Ithaca, NY, Cornell University Press.

• Sinclair, W.A. and H.H. Lyon. 2005. Diseases of Trees and Shrubs, 2nd Edition.  Ithaca, NY, Cornell University Press.

• Vittum, P.J., M.G. Villani, and H. Tashiro. 1999. Turfgrass Insects of the United States and Canada. Cornell University, Ithaca, NY.