2.1 Current Ten-Domain JTA Map

The Current JTA 2022 Domain Map

The International Society of Arboriculture (ISA) Certified Arborist examination outline is built on the Job Task Analysis (JTA) 2022. A job task analysis is a survey of working arborists worldwide; ISA then weights each domain by how frequently and how critically practitioners perform those tasks. That is why this is an applied arboriculture exam, not a vocabulary quiz. Every question maps to a real decision a Certified Arborist must make in the field.

The outline contains exactly 10 weighted domains that sum to 100%. Memorize this table cold before you open any technical chapter:

Why the Question-Count Conversion Matters

The exam has 200 multiple-choice questions, but only 180 are scored (20 are unscored pretest items). Applying each domain weight to the 180 scored items gives the column above. This is the single most useful translation you can do: it shows that Safe Work Practices and Pruning together carry roughly 52 scored questions — nearly 29% of your graded score — while the smallest domain, Urban Forestry, contributes only about 11.

The four largest domains (Safe Work Practices 15%, Pruning 14%, Tree Biology 11%, Tree Risk 11%) account for 51% of the scored exam, so a candidate who masters those four is already most of the way to the 76% passing standard (152 of 200 correct).

How to Use the Map

• Build notes by domain. Put every concept, worked example, and missed practice item under one of the 10 headings. When a topic spans several domains (a storm-damaged maple over a sidewalk touches Tree Biology, Pruning, Tree Risk, and Safe Work Practices), record the cross-links explicitly — the exam loves integrated scenarios.
• Audit your resources against this table. Older ISA outlines and many third-party study guides divide the work differently or use stale weights. If a resource's domain list does not match this exact 10-row map, it may still teach sound arboriculture, but it must not control your study calendar.
• Respect breadth. A skilled climber still needs Soil Management and Urban Forestry; a plant-health-care technician still needs Pruning objectives and work-zone safety. The Certified Arborist credential certifies the whole decision chain, not one specialty.

A common trap is treating the small domains as optional. Soil Management (7%) silently drives planting depth, establishment irrigation, diagnosis of chlorosis, and construction root-zone protection. Urban Forestry (6%) covers inventories, ordinances, canopy goals, tree value (appraisal), and public communication. Skipping either domain forfeits roughly two dozen scored items between them — more than enough to fail a candidate sitting near the cut score.

What Each Domain Actually Tests

To turn the table into a study plan you need to know what lives inside each heading. The 10 domains break down roughly as follows:

• Tree Biology — anatomy of roots, trunk, branches, and leaves; xylem and phloem transport; photosynthesis, respiration, and energy allocation; the response to wounding (compartmentalization), growth regulation, and tree development over time.
• Tree Identification and Selection — leaf, bud, bark, and form characteristics; matching species to soil, space, hardiness zone, and pest pressure; right-tree-right-place decisions.
• Soil Management — texture, structure, drainage, pH, organic matter, compaction, soil volume, and fertilization based on need rather than habit.
• Installation and Establishment — nursery stock quality, root-flare placement, planting-hole geometry, mulch, staking, and post-planting irrigation through the establishment period.
• Pruning — objectives, cut location at the branch collar, dose, timing, and the differing needs of young and mature trees.
• Diagnosis and Treatment — distinguishing signs from symptoms, biotic versus abiotic causes, and integrated pest management before treatment.
• Trees and Construction — impact prediction, tree protection zones, root and soil preservation, and post-construction recovery.
• Tree Risk — targets, site, defects, likelihood and consequence of failure, and mitigation.
• Safe Work Practices — job briefings, electrical hazards, personal protective equipment, equipment inspection, work-zone control, and emergency response.
• Urban Forestry — inventories, canopy assessment, ordinances, community engagement, and tree appraisal.

Notice how often the same underlying knowledge — soil, biology, and safety — recurs across domains. That overlap is the reason the question-count column above is a planning aid, not a ceiling: a strong soils foundation earns points inside Installation, Diagnosis, and Construction items even though those questions are not counted under Soil Management. Treat the map as the skeleton of your notebook, then let the cross-domain connections become the muscle that carries you through integrated scenarios on test day.

Eligibility and Where the Map Fits

Before the domain map matters, you must qualify to sit the exam. ISA requires a combination of experience and education — commonly three years of full-time eligible arboriculture work experience, with reductions available for relevant degrees or coursework. The Certified Arborist credential is the foundational ISA certification; more advanced credentials such as Board Certified Master Arborist build on it. The domain map you just learned is the published content outline for this foundational exam, so it is the correct organizing structure for every candidate regardless of how they qualify.

Confirm your specific eligibility pathway in the current Program Guide, then return to this map as the backbone of all your study notes — it remains stable across editions even when individual question wording changes.