Fall time foliage

Right now, it is amazing to look outside and see all the splashes of red, yellow, orange, and green that the trees are providing us with. This beautiful scenery is one of the multiple reasons living in the country in Indiana is great. Yet the question does remain, what causes leaves to change into various shades of red, yellow, and orange?

Chemistry is the driving force behind the leaves changing colors. Throughout the summer, chlorophyll gives leaves their green color and is essential in the photosynthetic production of food needed by the tree. Once the days grow shorter and temperatures begin to fall, chlorophyll production slows down. When this occurs, other pigments begin to appear giving leaves their brown, red, orange, purple, and yellow hues. 

The color the leaf takes on depends on which chemical is more prominent: anthocyanin, carotene, xanthophylls, or tannin. It is never completely certain which chemical will be more prominent, but tannin is more prevalent in the brown to dark red leaves of oaks, walnuts, and hickories. When leaves start to change colors, the outer margins of the leave will change first. Slowly the color will move further into the leaf, leaving the midrib to be the last green segment. This is due to how the plant receives its nutrients from the roots and other parts of the tree. 

Temperature, light, and water supply are the primary factors that influence the pigment of the leaves resulting in no two autumns ever being alike. Red colors often develop on exposed leaves due to the bright light they receive. A similar result occurs when there is a mild drought. Color intensity will decrease if there are several rainy days near the peak of coloration. The biggest impact that weather has is delaying the onset of the fall colors due to a late summer drought. Therefore, it is generally said that the best fall foliage occurs when there is a dry, late summer with rain in early fall or when there is heavy rain and bright sunshine with the gradual drop in temperatures. 

The bad part about the leaves changing colors is that the color never lasts as long as we wish it would. Instead, the leaves eventually fall to the ground resulting in a yard that is covered in crumbly red, yellow, and orange decaying leaves.Fallen leaves can be a good item to compost since they have enough microorganisms on them to start the composting process fairly easily. If you add grass clippings to the compost, it will provide the added nitrogen needed to speed up the process. The resulting compost is great to use as a soil conditioner. Adequate moisture for composting leaves is about 40-60% moisture. Therefore, it is a good idea to wet the leaves in the compost. If too much moisture is provided, then the compost will begin to smell. To help with the composting process, it is best to turn the pile from time to time to allow air to enter it and the decomposing to occur. Similarly, the pile may need turned to maintain the proper temperature in the compost. 

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Upcoming Events:

Oct. 14 – Extension Office Closed in Honor of Columbus Day

Nov. 3 – Putnam 4-H Awards Program

Nov. 4 – Farmland Rental in Indiana, 6:30-8:30 pm, Extension Office, Register at
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Nov. 5 – Curb Your Urge to Splurge-Holiday Edition

Nov. 5 – Extension Office closed like all county offices for Election Day

Nov. 11 – Extension Office closed like all county offices for Veterans Day

Nov. 12 – Gourdiculture: Starting Seeds to Crafting, 7-8 pm, Community Building