by Randy Davis

It's the first of September and another growing season is beginning to come to an end. Here in the Mid-west, fall can sneak up on you and you won't even know it.  Next time you go outside to enjoy your trees take a cup of coffee with you, find a nice place to sit, and just spend some time looking at the trees in the natural landscape. Check out what's on the ground around you.  Is it hot? Do you feel a cool briskness on your skin that you haven't felt in a long time?  If you're like me and spend lots of time outside, you'll probably answer yes to both of those questions at this time of the year.  It's the early seasonal change into the fall season.  The Pine trees are starting to drop their 3 year old needles to the ground, the Black Walnut (Juglans nigra) leaves are beginning float slowly to the ground with the slightest of breezes. The wild mosses are beginning to take on that lovely deep brilliant green with the slightest amount of rainfall and the cooler night time temperatures. You'll even see some trees setting out new growth, albeit small weak growth. It's the response to the changing weather patterns.

For the novice, this time of the year can be very confusing; making the transition through this period into fall is often difficult and perplexing.  It's warm, so why aren't my trees growing like they did 2 months ago? The leaves of my deciduous trees are looking thin, tattered along the edges, and the soil is staying wetter longer than I'm used to.  Take a deep breath, sip on that coffee, and relax.  Mother Nature is doing her thing right now, and the trees that we love are taking action in response.  The conifers are beginning to shed their old foliage. You'll notice that pine needles are turning brown and dropping. All of the Chamaecyparis species are turning their old foliage yellow, which will soon turn brown and fall. Old growth on Junipers will begin to turn brown, yet hang on to the branches.  The deciduous trees are taking on that tired tattered look, and the inner leaves that received the least summer sun are beginning to drop off.  Now is the time for the novice to direct hih attention to the natural process which will guide him to a better understanding of pruning techniques and why in bonsai, we pinch, pinch, and pinch again during the active growing season.  Take the time to look at those conifers in detail and see where that 3 year old needle is.  Having a clear understanding of that will greatly enhance your ability to know what's going to happen next summer when you're pinching your trees for shape and ramification.

Don't be confused and think that those tattered, deciduous leaves mean that your tree is in trouble and may need an emergency repotting, it probably doesn't.  The leaves of deciduous trees are only meant for a single growing season, so it's natural for them to get tattered, torn, eaten, brown around the edges, and even filled with holes at this time of the year.  The ravages of the summer season with wind, dry air, and the plethora of insects are nothing but just a part of the normal process that deciduous trees are used to from Mother Nature.  On some trees, most notably the Maple genus (Acer), you will soon be anointed with the spectacular display of fall leaf coloration.

All of the trees and shrubs native to the temperate zones are preparing for the onset of winter by reducing the level of sap flow from the roots to the foliage.  It is most noticeable on the deciduous trees, but the evergreen conifers are doing it as well, at a slower rate.  While the summer months have been a process of the trees taking up water and food and converting it to sugars, the process is reversed at this time of the year.  As the sap flow slows down, the sugars in the foliage are being converted to starches and sent to the roots of the trees as a store of food for next spring's growth.  Water will begin to be expelled from the branches as a protection mechanism for those cold winter months ahead. As a result, leaves will be shed to the ground on most deciduous trees.  I should note, however, that there are some trees, particularly Oaks (Quercus) and Beech (Fagus), that will retain their leaves on the branches to protect the dormant buds during the cold of winter. In a nutshell that's pretty much what's going on, so don't get your undies all tied up in a knot about it.  Relax and take another sip!

Now don't get too relaxed.  While Mother Nature is taking its course of action, there are many things that we bonsai enthusiasts should be doing at this time of the year.  In the next few weeks as the deciduous trees shed their leaves so you can see the branch structure, it will be the prime time of the wiring season before you put your trees away for the winter.  If you think about it, the branches of the trees still have some water in them, making them pliable, and they will respond to repositioning extremely well right now.  As the water diminishes in the branches and they are subjected to the first frosts of the season, the branches will harden up which will help set the branches in place over the coming winter.
If you have flowering trees in your collection, now is a good time to give them a good shot of super phosphate which will help them set flowers next year.  It's also the time to prepare for giving those deciduous trees their first dormant spraying once the leaves have completely fallen off.  Prepare the winter storage place for your trees, and gather up that supply of pine needles for insulation if you store your trees outside.  There's plenty to do at this time of the year to keep your trees in good health, but don't forget to sit down once in a while and enjoy the loveliness of the fall weather.