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Question 1. Which part of a tree is primarily responsible for water and nutrient uptake from the soil? A) Leaves B) Roots C) Trunk D) Bark Answer: B Explanation: Roots are specialized for absorbing water and nutrients from the soil, which are then transported to the rest of the tree. Question 2. What is the main function of the phloem tissue in trees? A) Transports water upward B) Stores carbohydrates C) Transports sugars and other organic compounds D) Provides structural support Answer: C Explanation: The phloem transports sugars and other organic compounds produced by photosynthesis from leaves to other parts of the tree. Question 3. Which cell layer is responsible for the secondary growth (increase in girth) of tree stems? A) Epidermis B) Xylem C) Cambium D) Cortex Answer: C Explanation: The cambium is a layer of actively dividing cells that produces new xylem and phloem, leading to secondary growth. Question 4. What process describes the movement of water through a plant and its evaporation from aerial parts, especially leaves? A) Respiration
B) Transpiration C) Photosynthesis D) Diffusion Answer: B Explanation: Transpiration is the process by which water moves through a plant and evaporates from aerial parts, mainly the leaves. Question 5. In which part of the leaf does photosynthesis mainly occur? A) Epidermis B) Palisade mesophyll C) Spongy mesophyll D) Cuticle Answer: B Explanation: The palisade mesophyll is packed with chloroplasts and is the main site of photosynthesis in a leaf. Question 6. Which structure allows gas exchange between the internal leaf tissues and the atmosphere? A) Lenticels B) Stomata C) Bark D) Trichomes Answer: B Explanation: Stomata are pores on the leaf surface that allow for gas exchange, including CO₂ uptake and water vapor release. Question 7. Which of the following best describes the function of lenticels? A) Anchor the tree B) Gas exchange in stems and roots C) Water absorption D) Carbohydrate storage
Question 11. During photosynthesis, trees primarily take in which gas? A) Oxygen B) Carbon dioxide C) Nitrogen D) Methane Answer: B Explanation: Carbon dioxide is taken in through the stomata and used in photosynthesis to produce sugars. Question 12. Which process in trees releases energy by breaking down sugars, often producing carbon dioxide and water? A) Transpiration B) Respiration C) Photosynthesis D) Assimilation Answer: B Explanation: Respiration is the metabolic process by which plants break down sugars to release energy, producing CO₂ and H₂O. Question 13. Which of the following best describes “compartmentalization of decay” in trees? A) Absorbing nutrients from decaying matter B) Isolating damaged or decaying tissues with chemical and physical barriers C) Shedding leaves in autumn D) Growing new roots after injury Answer: B Explanation: Compartmentalization of decay involves the formation of barriers around injured or decaying tissues to prevent the spread of pathogens. Question 14. The CODIT model describes how trees respond to: A) Drought stress
B) Pruning wounds or injuries C) Fungal infections in leaves D) Changes in photoperiod Answer: B Explanation: The CODIT (Compartmentalization Of Decay In Trees) model explains the formation of physical and chemical barriers after wounding. Question 15. Which of the following is an example of vegetative growth in trees? A) Production of flowers B) Extension of shoots and roots C) Formation of seeds D) Leaf senescence Answer: B Explanation: Vegetative growth refers to the growth of non-reproductive parts like shoots, roots, and leaves. Question 16. The allocation of energy in a tree refers to: A) How photosynthates are distributed to different tissues for growth, storage, and maintenance B) The process of breaking down stored carbohydrates C) The absorption of water from the soil D) The process of gas exchange in leaves Answer: A Explanation: Energy allocation involves distributing products of photosynthesis to various functions such as growth, storage, defense, and reproduction. Question 17. Which phenomenon describes the seasonal timing of events such as bud break and leaf fall? A) Morphogenesis B) Phenology C) Phytoremediation
Explanation: The root cap contains statoliths that detect gravity, guiding root growth downward. Question 21. How do trees typically respond to mechanical stress, such as wind or heavy snow loads? A) By producing thinner stems B) By increasing growth of supportive tissues like reaction wood C) By reducing root growth D) By dropping leaves Answer: B Explanation: Trees develop reaction wood (tension or compression wood) to strengthen areas under mechanical stress. Question 22. Which adaptation is commonly seen in desert trees to conserve water? A) Large, broad leaves B) Thick cuticles and reduced leaf area C) High rate of transpiration D) Shallow roots Answer: B Explanation: Desert trees often have thick cuticles and small or no leaves to reduce water loss. Question 23. Palms differ from most trees in that: A) They have a vascular cambium B) They lack true secondary growth and wood C) They have broad leaves D) They have taproots Answer: B Explanation: Palms do not have a vascular cambium; they lack secondary growth and do not produce true wood. Question 24. Which adaptation is typical of tropical rainforest trees?
A) Thick bark B) Buttress roots for support C) Needle-like leaves D) Deep, narrow crowns Answer: B Explanation: Buttress roots provide stability in the shallow, nutrient-poor soils common in tropical rainforests. Question 25. Which of the following is NOT a function of leaves? A) Photosynthesis B) Water absorption C) Gas exchange D) Transpiration Answer: B Explanation: Leaves do not absorb water; this function is performed by roots. Question 26. Which leaf arrangement has one leaf per node, alternating sides along the stem? A) Opposite B) Whorled C) Alternate D) Palmate Answer: C Explanation: Alternate leaf arrangement has one leaf per node, alternating sides along the stem. Question 27. What is a key morphological characteristic used to identify tree species? A) Leaf margin B) Soil pH C) Root length D) Bark color only
A) Drupe B) Samara C) Capsule D) Berry Answer: C Explanation: Capsules are dry fruits that split open to release seeds, as seen in catalpa and some magnolias. Question 32. The silhouette of a tree refers to: A) Leaf shape B) Bark color C) The overall outline or profile of a tree D) Fruit color Answer: C Explanation: The silhouette is the outline of the whole tree against the sky, often distinctive for species identification. Question 33. What is a distinguishing feature of a palm leaf compared to a typical broadleaf tree? A) Opposite leaf arrangement B) Pinnate or palmate leaf structure C) Simple, entire margins only D) Needles Answer: B Explanation: Palms have fronds that are either pinnate (feather-like) or palmate (fan-like), unlike most broadleaf trees. Question 34. When choosing a tree for a planting site, which factor is MOST important to consider? A) The color of the bark B) Species' adaptation to site conditions (soil, light, space, etc.) C) The tree's age
D) Number of leaves Answer: B Explanation: Selecting a tree species well-suited to the specific site conditions ensures healthy establishment and growth. Question 35. Trees that are known to be allelopathic: A) Attract pollinators B) Release chemicals that inhibit growth of nearby plants C) Have compound leaves D) Require acidic soils Answer: B Explanation: Allelopathic trees, such as black walnut, release biochemicals that can suppress growth of other plants. Question 36. Which tree species would be most suitable for an urban planting site with limited rooting space? A) Bald cypress B) Silver maple C) Ginkgo D) Weeping willow Answer: C Explanation: Ginkgo is a tolerant species with a compact root system, making it suitable for restricted urban sites. Question 37. Which soil type is typically best for most tree species? A) Heavy clay B) Sandy loam C) Pure sand D) Rocky Answer: B
A) Increase root depth B) Combine desirable rootstock and scion characteristics C) Improve seed production D) Enhance leaf color Answer: B Explanation: Grafting unites a scion (above-ground part) with a rootstock to combine traits such as disease resistance and fruit quality. Question 42. In tree identification, which flower feature is often most useful? A) Flower color B) Flower structure and arrangement C) Location of flowers D) Size of the tree Answer: B Explanation: Structural features such as petal number, arrangement, and reproductive organs are key to accurate identification. Question 43. Which structure is responsible for the production of new roots in a cutting? A) Lenticels B) Meristem tissue C) Bark D) Leaf blade Answer: B Explanation: Meristematic tissues are capable of cell division and initiate the development of new roots in cuttings. Question 44. Which of the following is a DISADVANTAGE of using seed propagation for trees? A) High genetic variability B) Rapid growth C) Disease resistance
D) Uniformity in offspring Answer: A Explanation: Seed propagation results in genetically diverse offspring, which may not all have desired traits. Question 45. Which of the following is NOT a morphological characteristic used in tree identification? A) Leaf arrangement B) Bark texture C) Soil moisture D) Bud type Answer: C Explanation: Soil moisture is an environmental factor, not a morphological characteristic. Question 46. The main difference between a drupe and a berry is: A) Drupes have a hard stone (pit) inside, berries do not B) Berries have wings C) Drupes are always dry D) Berries are only red Answer: A Explanation: Drupes, like cherries and peaches, have a single hard stone, while berries have soft, fleshy interiors. Question 47. Which macronutrient is most important for promoting overall tree growth and leaf development? A) Potassium B) Nitrogen C) Calcium D) Iron Answer: B Explanation: Nitrogen is essential for vegetative growth and chlorophyll production.
B) 5.5–6.
C) 8.0–9.
D) 10.0–11.
Answer: B Explanation: Most trees thrive in slightly acidic to neutral soils (pH 5.5–6.5). Question 52. Urban soils often present which of the following challenges for tree growth? A) Low compaction B) High organic matter C) Soil compaction and poor drainage D) Uniform structure Answer: C Explanation: Urban soils are often compacted and poorly drained, restricting root growth and oxygen availability. Question 53. Mycorrhizal fungi benefit trees by: A) Reducing root growth B) Forming a symbiotic relationship that enhances water and nutrient uptake C) Competing with roots for nutrients D) Causing root diseases Answer: B Explanation: Mycorrhizal fungi form mutually beneficial associations with tree roots, extending their ability to absorb water and nutrients. Question 54. The cation exchange capacity (CEC) of a soil measures: A) The number of earthworms B) The ability of soil particles to hold and exchange nutrient ions C) The rate of water infiltration D) The soil’s acidity
Answer: B Explanation: CEC indicates how well soil can retain and supply essential cationic nutrients to plants. Question 55. What is the main function of soil buffering capacity? A) Maintain soil temperature B) Prevent rapid changes in soil pH C) Improve drainage D) Increase soil compaction Answer: B Explanation: Buffering capacity helps soils resist sudden changes in pH, protecting plant roots from acidity or alkalinity shocks. Question 56. Which soil amendment is most effective at improving drainage in heavy clay soils? A) Peat moss B) Sand and organic matter C) Lime D) Sulfur Answer: B Explanation: Adding coarse sand and organic matter improves aeration and drainage in clay soils. Question 57. Bulk density is a measure of: A) Soil color B) The mass of soil per unit volume, including pore spaces C) Soil organic matter D) Soil nutrient content Answer: B Explanation: Bulk density reflects soil compaction; high bulk density means less pore space for roots and air.
C) Magnesium D) Iron Answer: B Explanation: Phosphorus is vital for energy transfer, root development, and reproductive processes. Question 62. Which method is most effective for correcting compacted soils around established trees? A) Deep tillage B) Core aeration C) Applying heavy mulch only D) Irrigation Answer: B Explanation: Core aeration loosens compacted soils, improves root oxygenation, and facilitates water infiltration. Question 63. Which fertilizer type provides nutrients immediately upon application? A) Slow-release fertilizer B) Organic compost C) Quick-release (soluble) fertilizer D) Mulch Answer: C Explanation: Quick-release fertilizers dissolve rapidly, supplying nutrients directly to tree roots. Question 64. The presence of earthworms in soil generally indicates: A) High compaction B) Poor drainage C) Good soil health and structure D) Low fertility Answer: C Explanation: Earthworms improve soil structure, aeration, and nutrient cycling, signifying healthy soil.
Question 65. What is the main function of mulch in tree establishment? A) Provide nutrients only B) Suppress weeds, moderate soil temperature, and retain moisture C) Lower soil pH D) Increase evaporation Answer: B Explanation: Mulch conserves soil moisture, suppresses weeds, and protects roots from temperature extremes. Question 66. Which of the following is a potential risk of piling mulch against a tree trunk (“mulch volcano”)? A) Increased drought tolerance B) Encouraged root growth into mulch, potential trunk rot C) Improved root aeration D) Reduced pest activity Answer: B Explanation: Deep mulch against the trunk can cause roots to grow abnormally and increase risk of decay. Question 67. Which is the best depth for mulch around a newly planted tree? A) 1–2 inches B) 2–4 inches C) 6–8 inches D) 10–12 inches Answer: B Explanation: A 2–4 inch layer is sufficient to provide benefits without causing root or trunk issues. Question 68. What is the most important consideration when planting a tree in a new location? A) Planting as deep as possible
