Core Insights - The peak viewing period for autumn leaves in Beijing has been delayed by about a week this year due to unfavorable weather conditions and plant diseases [5][6][9] - The best viewing period for red leaves in major parks like Fragrant Hills is from October 25 to November 15, with a red leaf rate of up to 80% for certain species [5][9] Weather Conditions - The combination of high temperatures and prolonged rainy weather in September and early October has negatively impacted the color change of leaves [6][8] - Ideal conditions for leaf color change include significant temperature drops and strong sunlight, which were lacking earlier in the season [6][8] Plant Health Issues - The health of the yellow-leaf trees has been compromised by diseases such as powdery mildew and wilt disease, affecting their ability to change color [8][9] - The wilt disease is caused by a soil-borne fungus that has persisted in the soil for years, complicating control efforts, especially in mountainous areas [9] Viewing Opportunities - Despite the delay in red leaf color change, other colorful foliage can be found in various parks, including ginkgo and purple leaf plants, providing diverse viewing options [11][12][14] - The Olympic Forest Park is highlighted for its vibrant ginkgo trees, which have already turned bright yellow, attracting many visitors [11][12]