Why Soil Testing is Important for Tree Health In Northern New Jersey

While you enjoy the lush greenery of New Jersey’s forests, the true story lies beneath your feet. Soil, often overlooked, is the lifeblood of these majestic trees.

This article highlights the importance of soil sampling and soil testing in maintaining tree health. From identifying nutrient deficiencies to managing soil pH and dealing with soil compaction, we’ll guide you through the essential steps of soil testing.

Get ready to dive under the ground’s surface and discover how you can help prevent tree diseases and promote attractive growth.

In This Article

  • What soil testing is and how it differs from soil analysis
  • Why regular soil sampling in your northern New Jersey yard is a huge benefit – for you and your plants
  • What a soil sample analysis tells you and what to do with the results
  • How to recognize the common soil problems in northern New Jersey that affect your trees and shrubs
  • Why healthy soil is vital for the health and longevity of your trees

The Basics of Soil Testing

The soil in your New Jersey yard is more than just dirt; it’s a complex ecosystem brimming with life and nutrients essential for healthy tree growth. Knowing what’s in it can make a world of difference for your trees.

Soil testing is a fundamental step in assessing the health of your trees. It’s like a health check-up for the ground where your trees plant their roots. Without it, you’re essentially blind to what’s beneath the surface and are unable to address potential problems that could harm your trees.

What does a soil test measure?

A soil test measures various parameters that are essential for understanding the soil’s fertility and health. These measurements typically include:

  • Nutrient content: Soil tests report on the content of primary nutrients such as nitrogen (N), phosphorus (P), and potassium (K), as well as secondary nutrients like calcium (Ca), sulfur (S), and magnesium (Mg).
  • pH level: Soil pH is a measure of the acidity or alkalinity of the soil, which is crucial for understanding nutrient availability and its impact on plant growth.
  • Organic matter: The test measures the amount of organic matter in the soil, which is important for soil health and fertility.
  • Cation exchange capacity (CEC): CEC is a measure of the soil’s ability to hold and exchange cations (positively charged ions), which is important for nutrient retention and availability.
  • Other physical and chemical properties: This may include measurements related to soil structure, salinity, electrical conductivity, and the presence of other essential and non-essential nutrients.

By examining the nutrients and other substances in the ground, it’s possible to identify any deficiencies that might be affecting the vitality of your trees and shrubs. This information is important for making informed decisions about fertilizer and other soil applications, understanding soil health, and optimizing plant health while minimizing environmental impact.

It’s not just about nutrients, though. Soil testing can also reveal the presence of heavy metals or other toxins that could impact tree health. If you’re seeing poor growth or disease in your trees, the problem might be lurking in the soil.

So, don’t underestimate the power of a good soil test. It’s the key to unlocking the secrets of your soil and keeping your trees healthy. It’s one of those things that might seem like a hassle, but trust me, it’s worth it. Without it, you’re just guessing and that’s no way to ensure the best for your trees.

DID YOU KNOW? Soil is not an inert substance – it’s a living resource teaming with billions of bacteria, fungi, and other microbes that make up a symbiotic ecosystem upon which plants depend.

Arborist from Aspen Tree in northern New Jersey performing a soil test for pH level.

What’s the difference between soil testing and soil analysis?

A soil test is a traditional analysis of soil chemistry, providing a snapshot of the soil’s macro and micronutrient levels, pH value, and other essential parameters. It offers this-season recommendations for optimizing plant health and is primarily prescriptive.

On the other hand, soil analysis is a broader term that encompasses not only the chemical properties of your soil, but also its physical and biological condition. It is used to manage the soil and develop effective nutrient management plans. Unlike a soil test, which is more prescriptive, soil analysis is fundamental to many management decisions and enables the planning of cultivation and soil management actions.

In a nutshell:

  • A soil test focuses on specific chemical parameters used to provide immediate recommendations to improve tree and shrub health.
  • A soil analysis provides a more comprehensive understanding of the soil’s chemical, physical, and biological status, aiding in long-term soil and plant health management decisions.

How do I know if I should test the soil on my property?

We recommend regular soil sampling as part of any property maintenance program. However, if you’re not doing it on a regular schedule or haven’t done a soil test in a while, look for these telltale signs of poor soil health that indicate it’s time to send a soil sample to a soil testing lab.

  • Soil Erosion: Visible soil erosion, especially after heavy rainfall, can indicate poor soil health. Erosion washes away valuable topsoil, nutrients, and organic matter, affecting plant growth and ecosystem stability.
  • Compacted Soil: Soil compaction, characterized by hard or compressed soil, restricts root growth and reduces water infiltration. Compacted soil can lead to poor drainage, hinder nutrient uptake, and negatively impact the health of your trees and shrubs.
  • Signs of Nutrient Deficiency: Nutrient deficiencies affect plant growth and overall vitality and are often a sign of poor soil. For example, yellowing leaves can suggest a lack of nitrogen, while a reddish-purple hue might point to a phosphorus deficiency. Stunted growth or smaller than normal leaves might mean there’s not enough potassium.
  • pH Imbalance: Soil pH plays an important role in nutrient availability for plants. Extreme pH levels (too acidic or too alkaline) can hinder nutrient uptake and affect plant growth. If not managed correctly, an improper pH level can stunt tree growth and lead to nutrient deficiencies. To ensure your trees are growing in an environment that suits them best, regularly test soil pH so you can identify and quickly address pH-related issues.
  • Weed Infestation: Weeds thriving in your garden can be a sign of poor soil health. Weeds often indicate disturbed or unhealthy soil conditions that favor their growth over desired plants.
  • Waterlogged Soil: If you notice areas with excess water accumulation it usually means the soil has poor drainage and there likely are soil structure issues. Waterlogged soil deprives roots of oxygen, leading to root rot and poor tree health.
A tree health technician from Aspen Tree applying a tree fertilization treatment based on the results of a soil test.

The tree health technicians from Aspen Tree apply tree fertilization treatments based on the results of a soil test to ensure each tree receives exactly what it needs.

How will soil sampling test results help me?

While a soil test provides valuable information about the nutrient content, pH, and other properties of the soil, it’s what you do with the information that makes the real difference. Visual indicators of probable soil problems are only a starting point; soil analysis provides the additional information needed to fully understand the condition of your soil and take decisive action.

Here are four of the most common benefits of using soil sample data to guide your tree and shrub care decisions:

  1. Optimizing tree and shrub health: Soil test results help determine the specific fertilizer, the correct amount to apply, and other requirements for different plants, thus optimizing their growth and yield. Over-fertilizing can harm your trees more than help.
  2. Environmental protection: By identifying the soil’s nutrient levels, soil tests can help prevent the over-application of fertilizers, which can lead to environmental contamination through runoff and leaching.
  3. Diagnosing plant problems: In many cases of “DIY tree health diagnosis gone wrong” it’s the underlying issues, such as nutrient deficiencies, pH, and soil compaction, that lead to an incorrect diagnosis of tree health problems.
  4. Cost savings: By providing tailored recommendations, soil tests help homeowners and property managers save money by avoiding the unnecessary use of fertilizers and other amendments.

In summary, soil testing is important for informed and sustainable land use, efficient plant diagnosis and treatment, and environmental stewardship.

How often should you get a soil analysis?

Regular soil testing helps identify any nutrient deficiencies or excesses, as well as the presence of harmful pathogens.

You should get a soil test at least once every three years. This frequency can help you monitor changes in soil fertility and make informed decisions about nutrient management.

However, if you are actively amending your soil or have a problem area, you may want to test more frequently, such as annually.

We also recommended testing whenever there is a major change in the landscape plants you’re growing or if you notice tree health problems during the growing season.

What time of year is best for soil sampling?

Soil sampling can be done at any time but we recommend doing it in early spring or in the fall, with fall soil testing allowing for results to be ready in time for the next growing season. Soil testing can provide guidance on pH levels, nutrient content, and recommendations for lime and fertilizer applications, which can save money and prevent environmental issues related to over-fertilization.

Soils & Soil Problems in Northern New Jersey

What kind of soils do we have in northern New Jersey?

Northern New Jersey is characterized by various soil types with different properties that can impact tree growth. Rockaway series soil, a brown, gravely loam, is the most common soil type found in northern New Jersey (including major sections of Hunterdon, Mercer, Union, Essex, and Bergen counties). In Bergen county, we have three dominant soils, including the acidic Booton series soil which can affect the availability of nutrients for plants, trees, and shrubs.

FUN FACT – Just like New Jersey has a state tree (the northern red oak) it also has an official state soil. Downer soils are sandy, yellowish soils found throughout much of the southern part of the state, particularly in the Pine Barrens.

Soil erosion around the roots of a tree in Clifton, NJ.

What are some common soil health issues in northern New Jersey?

Some common soil health issues in northern New Jersey include:

  • Soil Erosion: Heavy downpours and increased precipitation in the region can lead to soil erosion, washing away nutrients and affecting soil structure. Sediment runoff into streams and lakes affects the health of our waterways and aquatic life, and removes vital soil components from the land.
  • Compacted Soil: Soil compaction, caused by factors like constant foot traffic, machinery, or heavy objects, can reduce pore space in the soil. Compacted soil hinders water and air infiltration necessary for plant growth, restricts root development, and limits the movement of beneficial soil organisms like earthworms.
  • Nutrient Runoff and Leaching: Excessive rainfall can lead to nutrient runoff from soils into water bodies, affecting water quality, contributing to environmental issues such as algal blooms, and reducing soil fertility.
  • Poor Drainage / Waterlogged Soil: Soil with poor drainage can lead to waterlogging, which negatively impacts plant growth by depriving roots of oxygen. Improving drainage through proper soil management practices is essential for healthy plant development.

Addressing these soil health issues through proper management practices like erosion control, soil aeration, organic matter addition, and pH adjustment can help improve soil quality, support plant growth, and enhance the overall health of ecosystems in northern New Jersey.

How do I know if the soil in my northern NJ garden is good or bad for the health of the trees on my property?

To determine if the soil in your garden is suitable for the trees (and other plants) on your property, we recommend these steps:

  • Conduct a Soil Analysis: Send a soil sample to a testing lab for a complete soil analysis to assess the soil’s pH, nutrient levels, and other essential parameters. This will provide valuable insights into the soil’s health and guide you on necessary improvements for tree growth.
  • Observe Soil Characteristics: Take note of the soil’s color, texture, and structure. Healthy soil is typically dark brown, soft, and crumbly, indicating good health. Compacted or hard soil may hinder tree growth and nutrient uptake.
  • Check Soil pH: Soil pH is crucial for plant growth as it affects nutrient availability. Most plants prefer a pH range of 6.1 to 6.8. Understanding your soil’s pH can help you determine if it is suitable for tree health or if adjustments are needed.
  • Assess Drainage: Poor drainage can lead to waterlogging, affecting root health and nutrient uptake. Ensure that your soil has adequate drainage to support tree growth.
  • Look for Soil Organisms: Healthy soil is teeming with beneficial organisms like earthworms that contribute to soil health. The presence of these organisms indicates good soil quality.

These steps will help you evaluate whether your soil is suitable for the trees and other plants in your garden and make informed decisions to improve soil quality and promote healthy tree growth on your property.

Does soil sampling help identify soil compaction?

Soil compaction is another soil factor that can negatively affect tree growth. It can sometimes be identified visually, but soil sampling is a far more accurate way to evaluate compaction in soil.

Healthy soil typically has 40-50% pore space. When soil is compacted, such as by constant foot traffic, machinery, or heavy objects, the component parts are pressed together and the soil loses pore space. Without pores, soil cannot hold the water, nutrients, and air that trees need for healthy growth, leading to stunted tree growth and poor overall health. Earthworms and other soil organisms cannot move freely through compacted soil, and plant roots are unable to penetrate it.

How do I know if the soil in my northern NJ yard is compacted?

To determine if the soil in your northern New Jersey yard is compacted, look for the following visual signs:

  • Unusual Soil Appearance: Look for signs of compaction such as surface crust, “platy” soil structure resembling stacked plates, or large dense clods.
  • Poor Drainage: Compacted soil often has poor drainage due to reduced pore space, leading to water pooling on the surface rather than infiltrating into the ground. If you notice water pooling or slow absorption after rainfall, it could indicate soil compaction.
  • Reduced Plant Growth: Plants struggling to grow or showing signs of stress, such as stunted growth or yellowing leaves, can be a sign of compacted soil. Compacted soil restricts root development and nutrient uptake, affecting tree growth and overall health.
  • Presence of Specific Weeds: Some weeds, such as Ground Ivy (Creeping Charlie), Annual Sow Thistle, and Japanese Knotweed thrive in compacted soil conditions. If you notice these noxious plants taking over your yard, it’s a pretty good sign that the soil isn’t
  • Observation of Soil Structure: Check the structure of the soil by digging a small hole. Compacted soil may lack visible pore spaces and will be tightly packed.

Beyond the visual cues that indicate possible soil compaction, you can perform several simple tests to confirm your initial diagnosis.

  • Soil Hardness Test: Compacted soil feels hard and dense to the touch but that’s not always a reliable indicator of soil compaction. Instead, use a probe or a wire flag to assess soil hardness. Push the probe or wire into the soil and measure how deep it can penetrate. If the probe goes in easily to a depth of 12 inches or more, the soil is likely not compacted. If it reaches between 4 to 12 inches without bending, the soil condition is fair. However, if it bends at less than 4 inches, the soil is considered compacted.
  • Digging Test: Use a shovel, spade, or trowel to dig into the soil in suspected compacted areas. If the soil is hard and resistant to digging, exhibits a surface crust, or has dense clods, it may be compacted.
  • Soil Smell Test: Smell your soil after digging. Healthy soil should have an earthy and fresh smell. Foul odors like rotten eggs can indicate poor drainage due to compacted conditions.

PRO TIP: Test for soil compaction when the soil is moist but not saturated. Moist soil that is hard and difficult to dig through or break up may indicate compaction. Avoid testing dry soil as it will always seem harder.

Healthy Soil Leads to Healthy Trees

Don’t wait until your trees show signs of stress. By regularly sampling and testing your soil, you’re not just ensuring the health of your trees today, but you’re also investing in their longevity and vitality for years to come.

If you’d like to ensure your trees, shrubs, and landscape plants are set up to thrive, call the experienced, local arborists at Aspen Tree at (201) 939-8733 to schedule a property inspection, perform soil testing, and provide you with a thorough soil analysis and recommendations. Your trees will thank you!

Casey Walentowicz

Casey Walentowicz founded Aspen Tree Services in 1986 in Clifton, New Jersey, and specializes in residential, Commercial, municipal, HOA, and utility-related tree service. He’s a 2nd generation arborist who’s devoted his career to furthering his knowledge of tree care, urban forestry management, and technical operations in the tree service industry. Learn more about Casey