White Paper: Growth Patterns and Biodiversity Observations of Crataegus Monogyna (Hawthorn)
Executive Summary
This white paper presents a comprehensive analysis of Crataegus monogyna (common hawthorn) based on field observations conducted over a 2-hectare area. The study focuses on growth patterns, seed dispersal mechanisms, and interactions with the local environment. Key findings include the resilience of the species, its ability to thrive in challenging conditions, and its potential impact on land management practices.
Introduction
Crataegus monogyna, commonly known as hawthorn, is a deciduous shrub or small tree native to Europe, northwestern Africa, and western Asia. This species is known for its ecological importance, providing food and shelter for various wildlife species. This study aims to provide insights into the growth and spread patterns of C. monogyna in a specific 2-hectare area, with implications for land management and conservation efforts.
Methodology
The study was conducted through direct field observations over an extended period of 2 years. The 2-hectare area was divided into sections, including areas where hay is annually cut for cattle (marked in red). Observations focused on tree age, growth patterns, seed dispersal mechanisms, and interactions with local fauna and other plant species. Crataegus monogyna presence on the land is marked with purple and letters A-H. Gray arrows on the land indicate the downhill direction.
1. Seed Dispersal and Growth Patterns
C. monogyna primarily spreads through seeds, with 100% of new growth originating from seeds tumbling downhill or falling near parent trees.
The radius of seedling distribution is approximately 20 meters downhill and 2-4 meters uphill from mature trees.
Birds play a crucial role in seed dispersal, often causing fruits to fall near the parent tree while attempting to eat them. This behavior likely contributes to the lateral expansion of the species. Because of the bigger seed inside, it is impossible for small birds to collect the fruit, and most likely the fruit will fall from the bird's beak.
Seed will appear starting year 6, when the tree reaches at least 180-200 cm height.
2. Age and Growth Characteristics
The oldest identified tree has a diameter of 18-20 cm, with an estimated age of 20 years, and is positioned in Section A.
Younger trees (8-12 years old) were observed in multiple locations (B,D,E,G) across the study area.
Thorns develop starting from the second year of growth.
Fruit production is not very significant, but will keep the fauna occupied. (see table below)
3. Resilience and Adaptability
C. monogyna demonstrates remarkable adaptability, being the only bush/tree species observed growing underneath Black walnut trees, despite unfavorable soil conditions coming from juglone presence. The image below shows 13 seedlings (6 months) sprouted on a surface of 1sqm, between the black walnut leaves in the S-W side of area B.
First-year seedlings appear unaffected by grazing from sheep, cows, or goats.
The species shows resilience to cutting, with older seedlings (20-30 cm) developing laterally or producing new sprouts from roots when cut at the top.
4. Root Development
Early root development primarily relies on the principal tap root.
5. Implications for Land Management
Control Measures: Annual cutting in the first two years of development may effectively control the spread of C. monogyna in managed areas.
Grazing Impact: The apparent unpalatability of first-year seedlings to livestock suggests that grazing alone may not be an effective control method.
Soil Erosion Control: The species' ability to spread downhill and establish in challenging conditions could be beneficial for soil erosion control on slopes.
Biodiversity: C. monogyna's resilience and ability to grow in diverse conditions may contribute to increased biodiversity, especially in areas where other species struggle to establish. Bears tend to eat from the lower branches, but will not climb it because of the thorns
Cover Crop: Because of the thorns, the tree is perfect for creating natural barriers from bigger wild animals (bears, wildhogs, etc)
6. Conclusion
Crataegus monogyna demonstrates remarkable adaptability and resilience in the studied environment. Its growth patterns, seed dispersal mechanisms, and interactions with local fauna highlight its ecological importance. Its potential benefits for erosion control and biodiversity should be considered in conservation and land-use planning.
7. Recommendations
Implement C. monogyna as a cover crop and barriers for agroforestry, instead of posts, or electrical fences which severely affect the health and behavior of the native fauna.
Consider utilizing C. monogyna for soil erosion control on slopes and in areas with challenging soil conditions.
Further study the species' interactions with local wildlife and its impact on overall biodiversity.
Investigate the potential for integrating C. monogyna into agroforestry systems, given its ability to coexist with other tree species like walnuts.
By understanding and leveraging the unique characteristics of Crataegus monogyna, forest owners, land managers and conservation professionals can make informed decisions to balance ecological benefits with land-use objectives.
Author: Stefan A.
