Riddle #9 - Our journey through the layers and their functions in a tree trunk culminates with the innermost components. We’ll go easy on this one - just name them!

Answer: Growth in the diameter of plants is due to the cell divisions in the cambium, an extremely thin cylinder of meristematic tissue found just under the bark. New cells are formed on both sides of the cambium each year. Those to the inside make up the xylem, which conducts water and nutrients; and those to the outside make up the phloem, which transports sugars, amino acids, vitamins, hormones, and stored food. In the xylem, the fibers provide strength and the vessels allow water and nutrient flow to the leaves.

More explanation about our three riddles around the components of tree trunks can be found at:

• Tree Trunk from Iowa State University Extension at https://naturalresources.extension.iastate.edu/forestry/tree_biology/101.html
• Minnesota DNR's Minnesota Forest Treasures: www.dnr.state.mn.us/forestry/education/foresttreasures/partsofatree.html

Riddle #8 – September 2022

Now that we’ve got that girth thing figured out, let’s take a closer look at this vital component of a tree trunk. That vascular or cork cambium produces conducting cells in two layers. What is the outer layer called and what its function? Ditto for the inner layer?

​Answer: The outer layer is phloem, sometimes referred to as the inner bark, the vascular tissue that conducts sugars and other metabolic products downward from the leaves.
The inner layer is xylem, located toward the inside of the cambium layer. Xylem is the vascular tissue through which most of the water and minerals of the tree are conducted.

 Riddle #7: Ever wish your expanding “girth” could garner the same appreciation accorded to the DBH (diameter at breast height) of trees? One reason starts with a thin layer of cells that contributes to the expanding girth of a tree and ultimately produces its bark. What is that layer called? Succeeding riddles will delve deeper!
Answer: The cork cambium contributes to the expanding girth of a tree. The cork cambium is a thin layer of cells that ultimately produces the bark of the tree.

Riddle #6: A distinctive feature of this native hardwood tree is “squarish stems”. Can you name the tree and perhaps two other distinctions for this tree?
Answer: Blue ash, Fraxinus quadrangulata The botanical name is from Latin “four-angled ash” referring to the squarish twigs. American settlers used a bluish color extracted from the twigs as a dye. Perhaps most interesting recently is the theory that healthy blue ash trees appear to have some resistance to the deadly emerald ash borer.  Learn more here:  
https://kimmerer.com/trees/blue-ash/
https://kimmerer.com/blue-ash-and-the-emerald-ash-borer/
and https://en.wikipedia.org/wiki/Fraxinus_quadrangulata

Riddle #6: What family of trees often retain their dead leaves after others have dropped them? And what is this phenomenon called?
Answer: Leaf marcescence common in the Fagaceae, the tree family that includes oaks, beeches and chestnuts, this function retains dead leaves on the tree well after other trees are completely bare. This is mentioned in our our book review of The Nature of Oaks, and on the kwoa.net website at Resources > Publications

Riddle # 4: With baseball season finally in play, this month’s Wood You Not Know It? riddle is a double header with the April quiz. As a noun it is “the scientific study of trees”. Its adjective form is “having the shape or form of a tree”. Extra credit for identifying a noun related to this word for “the science or technique of dating events, environmental change, and archaeological artifacts by using the characteristic patterns of annual growth rings in timber and tree trunks.”
Answer: Dendrology. The related term is dendrochronology. 

1. Dendro is the Greek word for “tree”.
2. Chron is the Greek word for “time”.
3. Ology is also Greek word for “study”.
4. So, putting them all together you have, dendrochronology meaning “using trees to study time”.

Wikipedia’s definition of Dendrochronology, or tree-ring dating, is the scientific method of dating tree rings, also called growth rings, to the exact year they were formed. As well as dating them, this can give data for dendroclimatology, the study of climate and atmospheric conditions during different periods in history from wood. 

Riddle #3: This word is defined as “resembling a tree in growth or appearance”. It takes on elevated meaning in a recently published book of poems by the first National Youth Poet Laureate. A derivation of this adjective names the state botanical garden of Kentucky.
Answer: ABORESCENT – resembling a tree in growth or appearance;
arbor – “tree” + escent – “growing into” Latin.

References: See the poem Arborescent I in Call Us What We Carry, a poetry collection by Amanda Gorman, published December 7, 2021 by Viking Press.

Derivation:  The Arboretum, State Botanical Garden of KY at UK. Robin Wall Kimmerer uses the term interarboration in discussion of the new Orion book Old Growth (Yale Forest Forum, 9/18/21 at https://yff.yale.edu/). She states that “Trees and forests grow us and grow through us. Old Growth is not about ‘trees,’ but about this tree and that tree as individuals.”

Riddle #2 – March 2022: What tree is named after [a body] part of a deer and why?,
Answer: Buckeye – got its name because the nut looks like the bright eye of a deer when laid in the palm with the fist closed around it so the seed peeps out from the circle formed by the index finger and thumb. From Old Growth: Buckeye by Scott Russell Sanders, 2021, Orion magazine, p.118.

Research: Ohio's nickname is "The Buckeye State" partially because many buckeye trees once covered Ohio's hills and plains. In 1953, the Ohio Buckeye, Aesculus glabra, was declared Ohio's official state tree. The name "buckeye" stems from Native Americans, who called the nut "hetuck," which means "buck eye" (because the markings on the nut resemble the eye of a deer). The Ohio Buckeye is also commonly found in Kentucky woodlands.

Alternate Answer: Several people suggested Staghorn Sumac. Although the puzzle was aiming for Buckeye, we certainly agree that the alternate answer is acceptable. Forking structure and the velvety hairs covering the berries resemble a stag's horns, thus the common name.

Riddle #1 - February 2022: What looks like bacon, tastes like meat and grows like a cottony web underground? With its help a tree can greatly increase its functional root surface. These fungal threads are better appreciated above ground by wild mushroom hunters as porcini, cepe or bolete. Now some producers of plant-based meats are growing them in layers in fermentation tanks using only water, sugar and nutrients. The resulting slab has only a few processing steps and the texture of a cut of meat. Vegan never tasted so good. So, at your next Meatless Monday dinner, say “I’ll have the ???, please mam.” ANSWER: Mycellium 
Research Background: Peter  Wohlleben in The Hidden Life of Trees Pages 50-51. Fungi cell walls are mode of chitin – substance never found in plants – which makes them more like insects. In addition, they cannot photosynthesize and depend on organic connections with other living beings they can feed on. A fungus’s underground cottony web is known as mycelium. With the help of mycelium of an appropriate species for each tree… a tree can greatly increase its functional root surface so that it can suck up considerably more water and nutrients. You find twice the amount of life-giving nitrogen and phosphorus in plants that cooperate with fungal partners than in plants that tap the soil with their roots alone.
The fungal threads grow into the tree’s soft root hairs. The fungus also allows its web to roam through the surrounding forest floor. It connects with other trees’ fungal partners and roots. And so a network is created and now it’s easy for the trees to exchange vital nutrients and even information – such as impending insect attack.
      In an interview on Milk Street Radio [Episode 601, 1/9/22 Technically Food: Inside Silicon Valley’s Mission to Change What We Eat] Larissa Zimbaroff explained that  the fungi demand payment in the form of sugar and other carbohydrates, actually demanding up to a third of the tree’s total food production in return for their services.
     Mycelium is the threadlike network under the forest floor. Its mushroom is the fruiting body above ground. Companies are growing it in steel fermentation tanks layer upon layer. The resulting slab can be cut like bacon, then soaked, flavored and colored to resemble red meat. The process uses only water, sugar and nutrients. Burgers produced by companies like Impossible Foods and Beyond Meat use genetically engineered hemoglobin for color. Or processing the starch, carbohydrates and protein in peas to eventually produce pea milk. Plant-based meat is really big ag – controlled by a few in the interests of a few.
“Here at Impossible Foods, our plant-based heme, in a protein called hemoglobin, is made via fermentation of genetically engineered yeast. Heme is also responsible for the unique flavors and aromas that make meat taste like meat.”
     Colorado-based startup Meati-Foods harvests a fast-growing strain of mycelium from grasslands around the world. It is put into big metal tanks with sugar and left for 18 hours. The result is easily mouldable chunks that mimic the texture of real meat.
As nouns the difference between mycelium and mycorrhizal fungi: mycelium is the vegetative part of any fungus, consisting of a mass of branching, threadlike hyphae, often underground while mycorrhiza is (biology) a symbiotic relationship between the mycelium of a fungus and the roots of a plant.
The mycorrhizal fungi are made up of a root-like structure and possess a network of myceliumexternal to the tree roots that extends into the soil.
     The word “mycorrhiza” means fungal root. The fungus, because it does not photosynthesize, cannot fix its own carbon. Consequently, it receives all of its necessary carbohydrates from the host plant. In return, the mycorrhiza absorbs nutrients from the soil which are passed along to the plant.
– Karen Delahaut, University of Wisconsin – Madison