San Marcos Design Manual (March 16, 2021)

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Planting Guidelines

Article 4: Definitions For the purposes of this Manual and interpretation of regulations, the following definitions shall apply: 1. ANSI. American National Standards Institute; standards used by the hor ticulture, forestry and landscape professionals to measure and evaluate trees. 2. Arborist, Certified. An individual who has demonstrated knowledge and competency through obtainment of the current International Society of Arboriculture arborist cer tification, or who is a member of the American Society of Consulting Arborists. A cer tified arborist can be found in the yellow pages of the local telephone book; or online through the Texas Chapter of ISA at www.isatexas.com or www.isa-arbor.com. 3. Boring. The practice of tunneling at a depth below the effective root system of a tree, generally at a depth of 18 to 24 inches, for running underground utilities where it is not possible to trench around the critical root zone of the protected tree. 4. Caliper. The minimum diameter of a tree as measured six inches above the ambient grade for trees up to and including four inches in diameter, 12 inches above the ambient grade for trees having a diameter exceeding four inches but not exceeding eight inches. 5. Compaction. Compression of soil structure of texture by any means that creates an upper layer that is impermeable. Compaction is injurious to roots and the health of a tree.

City of San Marcos Noxious & Invasive Species List Scientific Name Common Name Sorghum halepense Johnson grass Tamarix ramosissima Salt cedar Triadica sebifera Chinese tallow tree Vitex agnus-castus Lilac Chastetree *** Species on this list are known to have escaped landscape settings into greens spaces managed by the City of San Marcos. Preservation and planting of these noxious and invasive plants are strongly discouraged.***

6. Critical Root Zone. See Tree Protection Zone

7. Dangerous. See Risk Tree

8. Dead tree. A tree that is dead or that been damaged beyond repair or is in an advance state of decline (where an insufficient amount of live tissue, green leaves, limbs or branches, exists to sustain life) and has been determined to be such by a cer tified arborist. If the tree has been determined to be dead, remove is permitted. 9. Diameter at Breast Height (DBH). The diameter of the tree trunk at four and one half feet (or 54 inches) above

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San Marcos Design Manual Amended: March 16, 2021