- Author: Dr. Anthony Fulford
What is subsoil?
There are several layers (also known as “horizons” to soil scientists) that can be found when we dig deeper and deeper down into the soil. We can imagine all the individual layers of a soil stacked one on top of the other like a layer cake, this is called the soil profile. The surface soil is the uppermost layer of the soil profile, and the one we are most familiar with, because this is where most of the action takes place. Soil mixing with tillage, compost and fertilizer application, irrigation, plant root growth, and animal activity (including microbes) are mainly concentrated within the soil's surface layer. Additionally, decomposition of plant and leaf litter occurs most rapidly in the surface soil, this eventually leads to the formation of new soil organic matter. In comparison, the subsurface soil, or subsoil, is composed of one or more soil layers that lie below the influence of surface soil activities. There is not a consistent depth at which every surface soil layer changes into the subsoil layer(s), rather the subsoil occurs at a different depth from place to place depending on numerous factors, including some of the factors mentioned previously. This is the reason why it is difficult to determine where the subsoil layer begins in the soil profile.
What does subsoil contain?
What does subsoil look like?
What is subsoil used for?
In general, the subsoil is a less suitable medium for plant growth compared to surface soil because of some of the factors mentioned previously. There are properties of subsoil however that make it suitable for other uses such as a source of “fill soil” for “cut-and-fill” construction operations, as a source of clay for building materials, and as an absorption layer for on-site wastewater disposal.
What can home gardeners do to keep their subsoil in great shape year after year?
What is the substratum layer of soil? Does that layer affect gardening at all, and if so how?
What is the bedrock layer? Does that layer affect gardening at all, and if so how?
Bedrock is the bottom layer of the soil profile layer cake. The bedrock layer consists of solid rock that has not yet been exposed to the chemical, physical, and biological processes of the surface soil and subsoil. In some places, bedrock is the foundation from which the overlying soil layers developed, while in other places, the bedrock layer may have become “buried” by windblown sand or sediment. Bedrock does not directly influence plant growth, but it can determine the type of clay minerals found in different layers of the soil profile.
Dr. Anthony Fulford is the Area Nutrient Management and Soil Quality Advisor for Stanislaus, Merced, and San Joaquin Counties.
/h3>/h3>/h3>/h3>/h3>/h3>/h3>- Author: Anne E Schellman
The Benefits of Trees
Trees provide so much more than shade. Here are a few reasons trees are important, courtesy of the International Society of Arboriculture (ISA):
- Air-conditioning costs are lower in tree-shaded homes & businesses; heating costs are reduced.
- In workplaces with trees, people report decreased workplace stress and fatigue.
- Cleaner air: leaves filter the air we breathe by removing dust and other particles.
- Cooler environment: trees reduce heat in and around parking lots and paved areas.
Trees and the Drought
California residents are being asked to lower their water use by 15%. One easy way to do this is to turn off your sprinklers. But wait! What happens to the trees? Although they may look okay for now, the stress of going without water will take a toll. Lawns can be easily replanted and replaced, but trees take many years to become established.
What do Trees Need?
How Should I Water My Tree?
There is no “silver bullet” on how often or how much to water. This depends on many factors. Instead, after you water, take a shovel (away from tree roots) and check your soil. How deep did the water penetrate? Make sure water penetrates to a depth of 18” by digging with a shovel. Once that area is dry, water again.
Prioritize Watering Trees with the TRIC
For more information about the value of trees, visit the following resources.
Resources
California Center for Urban Horticulture. UC Davis. Tree Ring Irrigation Contraption. https://ccuh.ucdavis.edu/tric
International Society of Arboriculture (ISA). Trees are Good. https://www.treesaregood.org/Portals/0/TreesAreGood_Benefits%20of%20Trees_0321_1.pdf
Water Talk. Janet Hartin. Podcast Episode 21. https://water-talk.squarespace.com/episodes/episode-21
This article was originally published on July 26, 2021.
/h3>/h3>/h3>/h3>/h3>/h3>- Author: Denise Godbout-Avant
Plants
If you have the space, plant an oak tree! While it will take several years for the tree to mature, few plants provide more benefits to nature than an oak tree. One Valley oak tree can provide food, water, and shelter to approximately 350 vertebrate species and over 250 species of insects and arachnids.
Choose plants that bloom at different times of the year, to ensure something is always blooming during the different seasons thus providing nectar sources year-round. Include some plants which produce berries to provide food sources attractive to birds and insects.
Lawns lack variety, thus reducing your lawn space and replacing it with native plants will increase the diversity in your garden. Decreasing the frequency of mowing permits grasses to grow taller, allowing flowers to grow and bloom which would attract bees and butterflies. You can also sprinkle some daisy and clover seeds into your lawn to provide forage plants and flowers for many beneficial insects.
Water
Ponds with aquatic-loving plants can encourage amphibians such as salamanders or toads, or wetland insects such as dragonflies, to visit and set up their homes.
Butterflies engage in behavior called “puddling,” where they stop in muddy puddles for water and nutrients. You can recreate this by filling a terra cotta saucer with soil and pebbles, sink it into the ground and keep it moist. Again, change the water regularly.
Plants and rocks around the water source(s) provide shelter, camouflage, and spots for creatures like butterflies, lizards, or turtles who like to sun themselves near water.
Housing for Bees
Leave the Leaves
Leaving leaves as they drop from your trees and bushes provides food and shelter for a variety of living creatures including worms, beetles, millipedes, larvae of some butterflies and moths, toads, frogs and more. These in turn attract birds, mammals, and amphibians that rely on the smaller organisms as a food source.
Chemicals
One Step at a Time
Changing your garden into a wildlife haven will likely be a step-by-step process over a period of time. Building a garden attractive to wildlife will bring you the enjoyment of watching them and the knowledge you are helping wildlife thrive.
Resources listed provide information for ways to you to build a garden attractive to wildlife.
- Butterflies in Your Garden: https://ucanr.edu/sites/CEStanislausCo/files/345791.pdf
- Sustainable Landscaping: https://ucanr.edu/sites/stancountymg/Sustainable_Landscaping/
- Trees in Your Garden: https://ucanr.edu/sites/CEStanislausCo/files/341553.pdf
- Pollinator-Friendly Native Plants Lists: https://xerces.org/pollinator-conservation/pollinator-friendly-plant-lists
- UC IPM Statewide Integrated Pest Management Program: http://ipm.ucanr.edu/
- The Bee Gardener: The Cavities You Want to Have: https://ucanr.edu/blogs/blogcore/postdetail.cfm?postnum=12785
- How to Make and Use Bee Houses for Cavity Nesting Bees: https://beegarden.ucdavis.edu/wp-content/uploads/2018/04/How-to-build-and-use-bee-blocks.pdf
Denise Godbout-Avant has been a Stanislaus County Master Gardener since 2020.
/h3>/h3>/h3>/h3>/h3>/h3>Citrus trees are one of the most popular fruit trees grown in California. Not everyone can grow Lemons, limes, kumquats, pomelo, grapefruit, and oranges, just to name a few! The climate has to be just right, and the Central Valley of California is perfect for this crop.
We hope you will join us for an evening learning how to successfully grow citrus in your garden. We will discuss how to properly plant, water, and care for your tree, including when to fertilize, if and when you should prune, and also some of the common pests that cause problems for gardeners.
Where*: On Zoom. You will receive a link the morning of the class.
When: Tuesday, March 29, 2022 6:00-7:30 p.m.
Cost: Free
Register at: http://ucanr.edu/citrus/2022
Instructors: Master Gardener Tim Long and Master Gardener Coordinator Anne Schellman
- Learn tips for saving water in the landscape.
- Become enlightened about drip irrigation
- Hear about attractive, low-water use plants.
Sign up now to reserve your space!
Water Thrifty Landscaping
Where: Stanislaus County Agricultural Center, Harvest Hall, OUTDOORS. 3800 Cornucopia Way, Modesto, CA 95358
When: Tuesday, September 21, 2021
Time: 6:00-7:30 p.m.
Cost: Free
Instructors: Master Gardeners Tim Long and Roxanne Campbell
Questions? Email ucmgstanislaus@ucanr.edu
Sign up online at http://ucanr.edu/thrifty/2022 or call Misa at (209) 525-6800 to reserve your space.