ornimental hort 10/23

Dose of Milkweed and Its Uses

  • Milkweed Appearance

    • At this time of year, milkweed is not dramatic in appearance.

    • Some plants had one or two good specimens, but overall, they seemed finished for the year.

    • Recent plantings were not yet matured enough to provide substantial displays.

  • Milkweed Seed Characteristics

    • The seeds, when released from their pods, are surrounded by a fluffy substance.

    • Historical Use: During World War II, this fluff was utilized in making life jackets.

    • Seed Pods:

    • If the pods are green, they are not ripe enough to break open.

    • Once ripe, the pods do not open on their own, allowing for the collection of seeds.

  • Seed Harvesting Method

    • The fluff surrounding the seeds can be burned away to facilitate easier seed collection.

    • A metal container is preferred for burning the fluff, but due to convenience, a plastic container was used.

    • After several burns, the remaining seeds can be collected, while minimizing risks of melting the plastic.

  • Asclepias Tuberosa (Butterfly Weed) Details

    • The specific variety discussed is Asclepias tuberosa, generally referenced as butterfly weed.

    • Importance of seed conservation highlighted; seed packets can be expensive while a single specimen can produce a large quantity of seeds.

Upcoming Test on Climate and Temperature

  • Test Preparation

    • A test will address climate, temperature, and microclimates, likely covered quickly.

    • Student performance on previous tests was acknowledged, indicating preparedness.

  • Understanding Climate vs. Weather

    • Weather: Refers to day-to-day atmospheric conditions.

    • Climate: Represents long-term averages, like hardiness zones where specific plants can thrive.

    • Relationship established that climate dictates the environment, impacting plant growth substantially.

Plant Hardiness and Conditions

  • Definitions

    • Frost Hardy: Plants that can withstand low temperatures without dying.

    • Frost Tender: Plants susceptible to damage from low temperatures.

  • Frost and Freeze Concepts

    • Frost is defined as temperatures near freezing for less than 12 hours.

    • A freeze occurs when the temperature is at or below freezing for extended periods.

    • Temperature Definition Clarification:

    • Light freeze: 29 to 32°F, capable of killing tender plants.

    • Moderate freeze: 25 to 28°F, may cause mild destruction.

    • Severe freeze: Often referred to as a killing frost, causing widespread damage.

  • Effects of Climate Conditions on Plant Growth

    • Significant variations from year to year can lead to different outcomes in plant survival rates.

    • Reporting noted that this year, a white frost was observed on the expected date (October 10th), but it was not classified as a hard frost.

Impact of Environmental Factors on Plants

  • Microclimates

    • Certain environmental conditions, such as temperature and precipitation, significantly affect the growth and tolerance of plants.

    • Specific examples were given, illustrating how rainfall and temperature variations in previous years impacted plant health.

  • Plant Resilience and Yearly Changes

    • The impact of extreme winters on plant survival rates was discussed, particularly mentioning ornamental plants like cherry trees that suffered severe cold damage.

    • Many plants can suffer cumulative effects due to environmental stressors over time, not just from a single year's conditions.

Factors in Plant Hardiness and Climatic Influence

  • Historical Frost Dates

    • First frost and average frost-free days vary. Instructed to recognize critical dates like Mother's Day (around May 10) as a reference for planting timelines.

  • Orchard Management During Frosts

    • Strategies to manage and protect orchards against frost damage include covering plants, using wind turbines to maintain air flow, and employing water sprinklers to prevent freezing.

  • Preventing Frost Damage Techniques

    • Recommendations for preventing frost damage include:

    • Cloud cover can retain heat and prevent frost formation.

    • Wind can deter frost and keep temperatures steadier.

    • Old fashion methods like using orchard heaters (smudge pots) for localized heating and coverage.

Practical Application of Temperature Management

  • Irrigation

    • Using overhead sprinklers at freezing temperatures can protect plants by keeping ice wet, thereby utilizing the heat released during the freezing process to maintain temperatures at 32°F.

  • Commercial Applications

    • Retailer growers are highly attentive to temperature forecasts and will take direct action, like watering or using protective coverings, to manage their orchards and prevent loss.

Conclusion

  • A significant focus will be placed on understanding how temperature and unique environmental conditions significantly influence plant growth and harvesting strategies.

  • Students are reminded to review supplemental material available on PLATO which provides further insights into conifer biology and may appear on future assessments.