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Lichen the Little Things - by Ashley Conley, Water Center Educator

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Share this: December 2020 Newsletter Connecting Virtually As we go through the holiday season and approach the new year, many things look different, especially events. For staff at the Water Center, we are looking forward to connecting with you virtually and hope to provide more opportunities for volunteer events and other learning workshops in the future. We are all finding new ways to stay connected and support one another. Please take care of yourself and your loved ones during these unprecedented times. In the meantime, stay connected with the Water Resources Education Center virtually with our new videos and our Online Community Learning Page. Discover facts about your local watersheds, fish, birds, native plants and lots more. Facebook and Instagram are also great ways to uncover fun and interesting environmental tidbits. Thank you for your continued patience. Please feel free to email questions or comments to [email protected]. #StaySafe #StayHealthy #StayStrongVancouverWA Thank you Volunteers! During the past two months, the Water Center hosted four volunteer garden cleanup events. With the goal of becoming a mature demonstration garden for the Backyard Habitat Certification Program, we asked the community for assistance. Vancouver volunteers responded with enthusiasm and dedication! Following COVID-19 distancing and masking protocol, our dedicated volunteers were able to prune trees, remove large patches of invasive Himalayan blackberry and stomp out “Stinky Bob,” aka Herb Robert. We raked and utilized leaf litter as mulch, essentially tucking in our lovely plants for the cold winter months ahead. THANK YOU to all of you who came out with your helping hands! Even masked, the smiles in the eyes of volunteers and staff could not be hidden as we experienced the joy and healing of being outside in nature together. Update: December Volunteer Events Due to the increasing cases of COVID-19 in Vancouver, the City has made the decision to cancel all volunteer events until at least December 14. When we are able to do so, we will schedule more events for our community to give service in our gardens. If possible, we are hoping to have an event on December 19, so please check our webpage and the City’s online event calendar in the middle of December for updates. Lichen the Little Things - by Ashley Conley, Water Center Educator As winter solstice approaches, most of the deciduous trees and shrubs have dropped their leaves and are saving energy for their spring rebirth. While the landscape may seem barren, the nature wanderer still has plenty to observe outside. The little things take center stage and in the Pacific Northwest, lichen is one of the feature stories etched into the winter landscape. To the casual observer, the sea of green carpeting the trees, branches and rocks is often assumed to be moss. Moss is a type of non-vascular plant called a bryophyte. While much of the luscious green mat is indeed moss, an organism called Lichen: Pilophorus acicularis lichen is often mixed within the emerald green layer living on the same substrate. First and foremost, unlike moss, lichen is not a plant. Historically, lichens are a symbiotic relationship between a fungus and either algae or cyanobacteria. They are often described as fungi that have discovered agriculture. The fungus provides the structure of the lichen while the algae and cyanobacteria are capable of photosynthesis, thereby providing the lichen with its food. Current research by lichenologists show Moss: Polytrichum sp. that these relationships are more complex than we knew. Although most species of lichen (60%) in our region are a combination of fungus and green algae, it has been found that some species can have more than one fungal component and can contain both algae and cyanobacteria. They are like mini ecosystems wrapped into one organism! Our region’s mild climate is the perfect spot for lichens to thrive. From Alaska to northern California, about 1,000 species of lichen have been identified. Lichens can be divided into three main types based on their growth structure: foliose, fruticose and crustose. Foliose lichens are flat and “leafy.” They have a defined upper and lower surface. Fruticose lichens are 3-D and branching, often defined as “shrubby” lichens. They attach to the substrate at one point and branch out. Crustose lichens are, you guessed it, Foliose lichen: Peltigera neopolydactyla “crusty.” They grow directly on rock or bark and have an upper surface only. Lichens are special for myriad reasons. They play extremely diverse and important roles in the functioning of a healthy ecosystem. Lichens provide habitat, food and shelter for a variety of organisms including mammals, birds, insects and tardigrades. Their in-house photosynthesizers help reduce atmospheric carbon dioxide by converting it into carbohydrates. They are able to “fix” atmospheric nitrogen, making this hard to come Fruticose lichen: Usnea sp. by and essential nutrient available to plants. As pioneer species, lichen colonize rocks and assist in the chemical weathering process. Acidic secretions by the lichen slowly breaks the solid rock into soil particles. And perhaps most importantly, they act as environmental monitors and are key indicator species for air pollution. Many lichens are intolerant of poor air quality and only grow in areas with clean air. With the spread of the urbanized landscape, monitoring of lichen species can show how changes in air quality Crustose lichen: Multiple species on rock materialize over time. Observation of these sensitive species can help us change our behavior to help preserve the natural landscape. With their captivating shapes, colors and patterns, lichens produce some amazing eye candy for the nature observer. Whether you enjoy wandering in the rain or prefer to wait for those precious breaks in the cloud cover, enjoy the winter season with a few lichen walks. Bring a magnifying glass, and a camera if you have one, to experience up close and personal the amazing and tiny world of lichen. www.cityofvancouver.us/WaterCenter 4600 SE Columbia Way | P.O. Box 1995 | Vancouver, WA 98668 (360) 487-7111 | TTY: (360) 487-8602 | [email protected] Subscribe to our email list..
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