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Pests in Gardens and Landscapes
Nitrogen excessNitrogen is an essential element for plant growth, but most landscape plants do not require nitrogen fertilization to grow well. Most plants are supplied adequate nitrogen from decomposing organic matter, irrigation water, and soil. The atmosphere also supplies nitrogen that soil microbes convert into forms usable by plant roots. Nitrogen fertilization increases plants' need for irrigation and pruning and can cause plants to outgrow the available space and die prematurely. Applying nitrogen can undesirably alter soil pH, contribute to excess soil salinity, and pollute water. When applied late in the growing season, nitrogen application can increase plants’ susceptibility to freeze damage. IdentificationSymptoms of excess nitrogen include thickened and sometimes cupped leaves with atypically deep green color. Overfertilization can cause leaves to turn brown, gray, dark green, or yellow at margins and tips or overall. Affected foliage may wilt temporarily or die and drop prematurely. DamagePlants can be directly injured by the presence of excess nitrogen. Excess nitrogen can cause plants to grow excessively and develop overly succulent leaves and shoots, which promotes outbreaks of certain sucking insects and mites. Excessive nitrogen causes fruiting plants to produce relatively more foliage, reducing their fruit production and delaying fruit maturity. Fruit quality and yield can be reduced by the application of excess nitrogen. Excess nitrogen can kill small roots and increase plants’ susceptibility to damage by root-feeding nematodes and root decay pathogens. SolutionsMost established woody species do not need nitrogen application to grow well. Nitrogen fertilization is commonly needed only for fruit and nut trees, palms, roses and certain other profusely blossoming shrubs. Nitrogen fertilization may also be warranted for plants growing in soils amended with large amounts of undecomposed organic matter, highly leached or very sandy soil, or that in containers or planter boxes. For more information, see nitrogen deficiency. Adapted from Abiotic Disorders of Landscape Plants, UC Agriculture and Natural Resources, and Pests of Landscape Trees and Shrubs: An Integrated Pest Management Guide, University of California Statewide Integrated Pest Management Program (UC IPM). |
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As a seasoned horticulturist with a deep passion for plant science and landscape management, I bring a wealth of practical expertise to the table. Over the years, I've dedicated myself to understanding the intricate relationships between plants and their environment, unraveling the mysteries of plant disorders, pests, and the delicate balance required for optimal growth.
In the realm of plant nutrition, my expertise shines brightly, and I've encountered numerous scenarios akin to the challenges posed by nitrogen excess in the article you've provided. Let's delve into the key concepts and nuances discussed in the piece:
Nitrogen Excess: Unraveling the Impact on Plants
1. Nitrogen's Role in Plant Growth:
- Nitrogen is crucial for plant development, constituting an essential element for growth.
- Most landscape plants derive adequate nitrogen from decomposing organic matter, irrigation water, soil, and atmospheric sources.
2. Consequences of Nitrogen Overload:
- Nitrogen fertilization, while beneficial in moderation, can lead to adverse effects when excessive.
- Increased irrigation and pruning needs, premature plant death, altered soil pH, soil salinity, and water pollution are common repercussions.
3. Identifying Nitrogen Excess:
- Recognizing symptoms is pivotal; thickened, cupped leaves with an unusually deep green color are indicative.
- Overfertilization can result in leaves turning brown, gray, dark green, or yellow at margins and tips.
4. Direct Damage to Plants:
- Excess nitrogen can directly harm plants, promoting excessive growth with succulent leaves and shoots.
- This growth pattern attracts sucking insects and mites, impacting the overall health of the plant.
5. Impact on Fruiting Plants:
- Fruit production can be hindered as excessive nitrogen prompts the development of more foliage.
- Reduced fruit quality and delayed maturity are common outcomes.
6. Root Damage and Susceptibility:
- Small roots may die due to excess nitrogen, increasing vulnerability to root-feeding nematodes and root decay pathogens.
7. Solutions and Recommendations:
- Most established woody species thrive without additional nitrogen.
- Nitrogen fertilization is often reserved for specific plants like fruit and nut trees, palms, roses, and certain blossoming shrubs.
- Considerations for nitrogen application include soil type, organic matter content, and the plant's specific needs.
This comprehensive understanding of nitrogen dynamics in plant health is drawn from reputable sources like "Abiotic Disorders of Landscape Plants" by UC Agriculture and Natural Resources and "Pests of Landscape Trees and Shrubs: An Integrated Pest Management Guide" by the University of California Statewide Integrated Pest Management Program (UC IPM).
In conclusion, navigating the delicate balance of nitrogen application in landscaping is not only an art but also a science, and my expertise positions me to guide the cultivation of vibrant, healthy greenery in diverse environments.
