"E" Horizon?

[BostonBull]

I have 1 Dwarf rigid Hinoki Cypress in my perennil area. It is about 5' away from all other plants in the area. I have a Dogwood, Hydrangeas, Azaleas, and Spirea in this area also.

I am wondering if it is worth the time to put some pine needles under the mulch around this tre to try and achieve the "E" horizon that is common around evergreen conifers?

The soil pH is at 6.3 for this area and the sample I sent out to Umass came back with recommnedations of Sulfur, and a 10-6-4 fert in early spring.

 

[Elmore]

Got Me

Your guess is as good as mine...probably better. I would simply use the pine needles on top and be done with it. Pine straw is my preferred mulch.

E Horizon

This is an upland soil. The grey coloration of the E horizon could be confused with horizons having a depleted matrix. E horizons are very common in soils of temperate coniferous forests. They result from a process called podzolization. In this process, with the help of copious rainfall, dark minerals are leached or stripped (eluviated) from the E (or eluvial) horizon by organic acids from the forest floor. While some podzolized soils (also called spodosols) can be hydric, this one is not, and can be distinguished from a hydric soil or a soil with a depleted matrix by the presence of an orange, reddish or brown band of higher chroma in the horizon directly below the E horizon. A hydric mineral soil will maintain the low-chroma coloration throughout the lower horizons of the profile.

What the f...

 

[BonsaiJedi]

An 'E' horizon forms an areas with high rainfall and low clay. You can see 'E' horizons often in soil cutouts as a light layer between an A and B/C horizons that form as darker, smaller particles leach out leaving a sandy, lighter colored horizon. They are not something you could create artificially and are not really related to mulch types (they are related to volume of rainfall and soil texture) so mulch with pine straw for all the other good reasons instead.

 

[BostonBull]

I am studying for the MA Certified Arborist exam and the information in the MCA study guide says differently.

"In some soil profiles there will be an additional layer of soil between the A-horizon and the B-horizon. When Present this layer will be pale grey or beige and it is designated as the E-horizon. This layer forms most commonly in areas dominated by evergreen vegetation. The natural decomposition of evergreen needles/leaves releases acidic substances that cause the dark colored coatings of organic matter and iron to be stripped from the soil mineralgrains, leaving the soil pale in color.

I had to type this, I couldnt figure out how to copy and paste from a PDF.

So who is right on this matter? The MAA or BonsaiJedi? Or Both?

 

[BonsaiJedi]

I am studying for the MA Certified Arborist exam and the information in the MCA study guide says differently.

"In some soil profiles there will be an additional layer of soil between the A-horizon and the B-horizon. When Present this layer will be pale grey or beige and it is designated as the E-horizon. This layer forms most commonly in areas dominated by evergreen vegetation. The natural decomposition of evergreen needles/leaves releases acidic substances that cause the dark colored coatings of organic matter and iron to be stripped from the soil mineralgrains, leaving the soil pale in color.

I had to type this, I couldnt figure out how to copy and paste from a PDF.

So who is right on this matter? The MAA or BonsaiJedi? Or Both?

The definition from my "Elements of the Nature and Properties of Soils" book:
"E Horizons: Zones of maximum leaching (eluviation) of clay, iron, and aluminum oxides, which leaves a concentration of resistant materials, such as quartz, in the sand and silt sizes. An E horizon is usually found underneath an A horizon and is generally lighter in color than the horizons above and below. Such E horizons are quite common in soils that develop under forests, especially those with high annual rainfall. They rarely develop under grasslands."

All these definitions are correct. It is a lighter layer formed in the soil profile of natural forest stands due to heavy leaching (I've seen them in several hardwood forests here in MN as well as conifer stands). Soil horizons take hundreds to thousands of years to form.

Going to your original question, putting pine needles under a cypress to create an E horizon is a good idea from a mulching standpoint but don't expect it to form a distinct E horizon anytime soon. You could create an E horizon on your own by filling sand into the planting hole beneath the cypress as this is essentially what an E horizon is. Other than perhaps improving drainage an E horizon provides no real health benefit to the trees as all the nutrients have been leached out, leaving sand.

 

[DonnyO]

Dude, i think the bonzai jedi is showing you how the "force of arboriculture" WORKS. Study hard, young jedi, but excessively read into these questions, you must not.