Mixed Deck — All CHT Topics Flashcards

Damping-off in seedling production is caused primarily by:

Answer: Soilborne fungi like Pythium and Rhizoctonia under wet, warm conditions

Damping-off is caused by Pythium, Rhizoctonia, or Fusarium fungi that attack seedlings at or below the soil line in overly wet, warm propagation environments.

The primary purpose of bottom heat in a propagation bench is to:

Answer: Encourage faster root development by warming the root zone

Bottom heat raises the temperature of the rooting medium (ideally 65–75°F), accelerating callus formation and root initiation in cuttings.

A landscape technician notices an irrigation leak on a client's property not included in the current service contract. The best action is to:

Answer: Document it with a photo and notify the client promptly

Documenting and promptly notifying the client of observed issues protects both the client's property and the technician's professional standing and liability.

Girdling roots are a serious concern for trees because they:

Answer: Wrap around the trunk and restrict water and nutrient flow as the tree grows

Girdling roots encircle the trunk and progressively constrict vascular tissue as both trunk and root grow, eventually causing decline or tree death.

What is a recommended mowing height for most turfgrasses?

Answer: 2.5 to 3.5 inches

A mowing height of 2.5 to 3.5 inches is generally recommended for most turfgrasses because it promotes deeper root growth, which makes the grass more drought-tolerant and resilient. Taller grass blades also shade the soil, reducing weed germination and moisture evaporation. Mowing too short (like 1 inch or less) can stress the turf, making it more susceptible to diseases, pests, and environmental damage.

Which symptom is most characteristic of oak wilt disease?

Answer: Rapid wilting and bronzing of leaves starting at leaf tips, moving inward

Oak wilt (Bretziella fagacearum) causes rapid wilting and bronzing starting at leaf margins and tips, moving inward; red oaks can die within weeks of infection.

What is the primary advantage of drip irrigation over overhead sprinklers?

Answer: Delivers water directly to root zone with less evaporation

Drip irrigation delivers water slowly and directly to the root zone, minimizing evaporation losses and reducing foliar disease risk.

Turgor pressure in plant cells is caused by:

Answer: Water entering the vacuole via osmosis, pushing against the cell wall

When water enters the central vacuole by osmosis, it creates turgor pressure that keeps non-woody plant cells rigid and maintains wilting resistance.

A horticulture technician's estimate should include all of the following EXCEPT:

Answer: Competitor's pricing

A professional estimate is built on your own costs (labor, materials, overhead) and desired profit margin — competitor pricing is a market reference, not a line item in your estimate.

Evapotranspiration (ET) data is used in irrigation scheduling to:

Answer: Estimate how much water plants use and need to replace

ET values quantify water lost through evaporation and plant transpiration, helping irrigators apply exactly the amount needed to maintain soil moisture.

What causes 'dry spots' in an otherwise irrigated lawn?

Answer: Poor head-to-head coverage or clogged nozzles

Dry spots in irrigated turf typically result from inadequate head-to-head coverage, clogged nozzles, or misaligned heads creating gaps in the spray pattern.

When using pesticides near a water body, what is the most critical precaution?

Answer: Observe all buffer zone requirements on the label to prevent runoff into water

Pesticide labels specify buffer zones near water; respecting these distances prevents aquatic contamination, protects non-target organisms, and keeps applicators legally compliant.

Vermicompost is produced by:

Answer: Earthworms breaking down organic material

Vermicompost is the product of earthworms (typically Eisenia fetida) digesting organic matter, producing a nutrient-rich, biologically active amendment.

Which factor is most important when selecting plants for a site?

Answer: Soil, sunlight, and water conditions

The success of any plant depends on its suitability to the specific environmental conditions of the site. Matching a plant's needs for soil type, pH, drainage, sunlight exposure, and water availability to the site's characteristics is paramount for its health and long-term survival and thriving.

In nursery management, what does 'liner' refer to?

Answer: Young, rooted plant ready for transplanting to a larger container

A liner is a small, young rooted plant (plug or rooted cutting) used as the starting material for growing on into a finished nursery product.

Drip emitters are typically rated by their flow rate in:

Answer: Gallons per hour (GPH)

Drip emitters deliver water very slowly and are rated in gallons per hour (GPH), with common rates of 0.5, 1, and 2 GPH.

The Casparian strip, found in root endodermis cells, functions to:

Answer: Force water and ions to pass through cell membranes rather than between cells, allowing selective uptake

The Casparian strip is a band of waxy suberin that blocks apoplastic movement, forcing ions through the symplast where selective transport occurs.

The 'drip line' of a tree refers to:

Answer: The outermost edge of the tree canopy projected onto the ground

The drip line is the circular area on the ground directly below the outermost branch tips of a tree, approximating the extent of the root zone.

Which macronutrient is primarily responsible for promoting leafy, vegetative growth?

Answer: Nitrogen (N)

Nitrogen (N) drives chlorophyll production and cell division, making it the key driver of vegetative, leafy growth.

Air layering is best used for propagating plants that:

Answer: Are difficult to root vegetatively and have long, flexible stems

Air layering allows rooting to occur while the stem remains attached to the parent plant, making it useful for hard-to-root species with firm or woody stems.