The ISA Certified Arborist exam tests your knowledge across every discipline of professional tree care — from tree biology and soil science to pruning standards and risk assessment. Studying with a printable PDF lets you review on your own schedule, mark up pages, and revisit tricky topics without needing an internet connection. Our free CATS practice test PDF covers the same core domains tested on the official ISA examination, giving you realistic question formats and detailed answer explanations to reinforce your understanding before exam day.
Whether you are preparing for your first ISA credential or brushing up after years in the field, this downloadable resource is designed to match the scope and difficulty of the real test. Print it out, work through each section, and use the answer key to identify areas where you need more study time.
Questions on tree biology probe your understanding of how trees grow and function. You need to know the roles of the cambium layer (where new xylem and phloem tissue is produced), how xylem transports water and minerals upward while phloem distributes sugars downward, the concept of apical dominance and how it governs branching patterns, and the architecture of root systems including structural roots, fine feeder roots, and mycorrhizal associations.
You are expected to identify common deciduous and coniferous species by region and recognize the visual characteristics that distinguish them. The Visual Tree Assessment (VTA) methodology and TRAQ framework guide how you evaluate defects — cracks, cavities, included bark, root damage — and assign risk ratings based on likelihood of failure and potential consequences.
ISA pruning standards are heavily tested. Know the five pruning types, where and how to make cuts to avoid damaging the branch collar, and why flush cuts are no longer accepted practice. Tree installation questions cover proper planting depth (root flare at or above grade), mulching best practices (no volcano mulching), and when and how to stake a newly planted tree.
Soil texture, compaction, drainage, and pH directly affect nutrient availability. You need to understand how pH extremes lock out key nutrients and how to remediate compacted soils. Pest and disease questions focus on common fungal pathogens (Armillaria, Phytophthora, Dutch elm disease), boring insects (emerald ash borer, bronze birch borer), and bacterial diseases. Cabling, bracing, aerial rescue, and utility line clearance protocols round out the safety-focused portion of the exam.
If you want to practice in an interactive format before downloading the PDF, our online CATS practice test delivers instant scoring and answer explanations after each question. Use the online tests to get comfortable with the question style, then use this PDF to review at your own pace — away from a screen, on a job site, or during a study group session. Both formats draw from the same domain-aligned question bank, so switching between them reinforces retention across all ISA exam topics.
Try these questions from our free Certified Arborist Tree Service of Albuquerque practice tests. The correct answer and an explanation follow each question.
A certified arborist notices galls on the roots of a young Arizona cypress. The most likely causal organism is:
Answer: A. Crown gall (Agrobacterium tumefaciens)
Crown gall caused by Agrobacterium tumefaciens produces characteristic warty, tumor-like growths at the root crown and on roots of many woody plants.
A certified arborist is consulting on a new commercial landscape plan. According to Albuquerque's Water Conservation Landscaping Ordinance, what is the maximum percentage of the total landscaped area that can be planted with high-water-use turf and plants?
Answer: D. 20%
The ordinance mandates that for new developments, high-water-use turf or plants shall not cover more than 20% of the total landscape area to conserve water. This regulation is a cornerstone of the city's effort to reduce municipal water consumption, particularly for outdoor irrigation.
A soil test in an Albuquerque urban landscape reveals pH of 8.2. What amendment would an arborist most likely recommend to improve micronutrient availability?
Answer: B. Elemental sulfur
Elemental sulfur acidifies alkaline soils by being oxidized to sulfuric acid by soil bacteria, lowering pH and improving micronutrient availability.
A certified arborist is explaining to a client how trees move sugars from the leaves to other parts of the tree, like the roots and fruit. In this process, the mature leaves are considered a 'source.' What is the corresponding term for the roots, fruit, or growing tips that receive these sugars?
Answer: B. A sink
In phloem translocation, a 'source' is an area that produces or supplies excess sugars (e.g., mature leaves). A 'sink' is an area of active growth or storage that requires more energy than it produces, such as roots, developing fruits, or new shoots, and therefore imports sugars.
Take the full Certified Arborist Tree Service of Albuquerque practice test