Species of the Month

Yellow Garden Spider

Late Summer to early Fall is a big time for spiders, as many species are at their largest and most visible, prepared for seasonal mating. We've been seeing plenty of webs and spiders of all sizes around the Arboretum, including a handful of astonishingly large yellow garden spiders (Argiope aurantia) and common house spiders (Parasteatoda tepidariorum). Whether you find these arachnids unsettling, intriguing, or endearing, they are a sure sign of the season beginning to change. Learn a little about these spiders and see if you can spot one by their distinct yellow markings in your garden or around the Arboretum.

• Male yellow garden spiders are less than half an inch in size, while females can be over an inch long.
• These spiders can bite humans when harassed, but their venom is generally harmless. People describe their bite as similar to a bee sting.
• Yellow garden spiders tend to build their webs in protected areas near open fields, sometimes choosing eaves of buildings.
• Their webs are circular and can be up to two feet across.
• These spiders typically keep their webs in the same location for the full Summer.
• From the center of the web, a yellow garden spider can vigorously oscillate the whole web, which is believed to either ensure a caught insect is fully entangled or to deter predators.
• Yellow garden spiders don't tend to live in dense populations like some other orb weaving spiders, nor do they build and abandon many webs like other species.
• When preparing to breed, the male spiders search for female spiders and make a small web near or in the web of a female spider before courting her by plucking the threads of her web while ready to evade in case she attacks. After mating, the male spider dies and is sometimes eaten by the female spider.
• Their egg sacks can be up to an inch in diameter and typically contain nearly 1,000 eggs.
• When young spiders exit the sac in the Spring, they are so small that they appear like dust. Some stay nearby and some use a thin strand of silk to float on the breeze to a new location.
• Their prey includes insects as well as small vertebrates like lizards and birds.

Photo by Don Wirtala

We are delighted to announce the 2026 Mushroom Festival! Presented by Mount Pisgah Arboretum, Cascade Mycological Society, and Lane Community College on Sunday, October 25th 10 AM to 5 PM.

This year's poster features a moonlit Cascade chanterelle (Cantharellus cascadensis) with a black-tailed deer (Odocoileus hemionus columbianus) illustrated by the incredible Emily Poole.

The festival will feature hundreds of fantastic fungi on display, mushroom walks with local experts, live music, fresh apple cider, hayrides, a scarecrow contest, craft vendors, kids activities, community organizations, and delicious treats (with and without mushrooms)!

Tickets go on sale September 25th. Arboretum members always get free Festival admission, become a member anytime before the festival and get in free.

Volunteer at the Mushroom Festival and get free admission, a commemorative poster, and be a part of our incredible community who makes these events possible.

Volunteer Opportunities Galore!

Become a Nature Guide

Orientation: Wednesday, September 9th 3:30 PM - 4:30 PM

Spread the joy of nature by leading local elementary students on field trips in the Arboretum. Nature Guides are trained on local ecology, working with kids, plant and animal identification, and more. Nature guides typically volunteer for one field trip per week in the Fall and Spring seasons.

Volunteer with the Track Chair Program

Trainings: Wednesday, September 9th 11:00 AM - 12:15 PM &

Tuesday, September 15th 5:30 PM - 6:45 PM



Help check out our all-terrain track chairs for users!

Become an Arboretum Ambassador

Trainings: Wednesday, September 9th 5:30 PM - 6:30 PM &

Tuesday, September 22nd 10:30 AM - 11:30 AM



Train to be an Arboretum Ambassador! Ambassadors table on the weekend to greet the public with a friendly face, answer questions, share information about opportunities, and sell Arboretum memberships and merch.

Parking Lot Paving is Underway

Lane County Parks has kicked off construction for major parking lot improvements which include paving, installing accessible parking, new walkways, and a bus loading zone.

Construction is planned through October. Paving will be done in stages, so parking will remain open throughout construction as it is safe and available, but parking spots are limited and open parking is shifting frequently. We will continue sharing more details of the project and the construction timeline as information is available.

Questions can be directed to Lane County Parks at 541-682-2000

Oaks of the Land, Acorns for the People: Ecology and Sustenance of a Wild Local Food

Friday, September 11th, 12:00 PM - 6:00 PM 

Have you ever wanted to try eating acorns? We will explore the role of oaks in the more-than-human world around us, the botany and identification of oaks, and also how human needs can be met when we help take care of the oaks. The workshop offers perspectives on the role of oaks in Indigenous ecological science, foodways, and worldview. We will practice hands-on techniques using manual methods of processing, with the goal of making this widespread traditional food accessible to you. In a changing landscape, with oak ecosystems shrinking and an unpredictable climate, looking to our local oaks for sustenance is a truly sustainable solution to food security issues.

Instructors

Heron Brae, botanist, wild food teacher, and educator with Brae Botanical Ways.

Joe Scott, member of the Confederated Tribes of Siletz Indians and curriculum director for the Traditional Ecological Inquiry Program.

Upcoming Nature Tours

All guided tours start at the Mount Pisgah Arboretum Education Building. Pre-registration is required. Members and kids under 4 are FREE, Non-Members $5 per person.

Plant Ecology Tour: Edibles & Medicinals

Saturday, September 5th 10:00 AM - 12:00 PM

Dive into plants with forager and herbalist Logan Keister. Logan will guide participants throughout the walk on seasonally available edibles and medicinals. Learn about local ecology, how to be ethical foragers, and how to identify edible plants and their toxic lookalikes.

Mindful Meandering

Sunday, September 6th 9:00 AM - 11:30 AM

Join Julia Siporin for a 2.5-hour Awake in the Wild retreat at Mount Pisgah Arboretum. Through guided meditation, silent walking, and simple sensory awareness practices, you’ll have space to settle, listen, and reconnect with yourself and the living world around you.

September Bird Tour

Sunday, September 13th 8:00 AM - 11:30 AM

Join Mieko Aoki and Julia Siporin for their monthly bird tour intended for people with all levels of birding experience. We’ll use vocalizations, habitat, and behavior clues for identification of our year-round residents and fall migrants. Come discover the Arboretum’s avian diversity!

Insect Tour

Sunday, September 20th 10:00 AM - 12:00 PM

Open your eyes to the fascinating world of insects on this tour led by insect-enthusiast and Mount Pisgah blog author Karen Richards. We’ll look into the incredible adaptations of some creatures you may recognize, and no doubt learn about some lesser-known insects as well. Every insect tour is a mini-safari!

Weekly Office Volunteering!

Every Wednesday 1:00 PM - 3:00 PM

Come by the Arboretum on Wednesday afternoons to help with office tasks like mailing and prepping materials. 

No experience is required to volunteer. We will provide you with a parking pass. Volunteers should be comfortable with repetitive tasks and writing.

Upcoming Work Parties

Become a steward of the Arboretum by helping us improve and maintain our facilities and habitat during our Work Parties! 

During Work Parties, volunteers help us keep our trails, facilities, and park clean, accessible, and beautiful! No experience is required to volunteer on these days, and we will provide tools, gloves, and a parking pass. 

All work parties meet at the bottom of the parking lot near the shop. 

Water Garden Habitat Work Party

Saturday, September 5th 9:00 AM - 12:00 PM

Helping us remove woody vegetation throughout the water garden area. This work will help keep our trails and habitats from being encroached upon by excessive vegetration.

Tuesday Tenders Weekly Work Parties

Every Tuesday 10:00 AM - 12:00 PM

Help us care for the Arboretum and keep trail conditions good! At these weekly work parties, volunteers tackle tasks like light weeding, vegetation management along trails, mulching, watering plantings, and more. One Tuesday Work Party per month will now focus on maintaining our memorial garden.

Wildflower Garden Work Party

Saturday, September 26th 9:00 AM - 12:00 PM

Let's give some love to the Patricia Baker Wildflower Garden in the Arboretum! We will be weeding, mulching, and some light trail maintenance.

Get Involved

Want to make a difference in other ways? We are always looking for nature guides, trail stewards, park ambassador volunteers, and many other roles. Let's talk about how you can get involved with the Arboretum.

Learn more about some of the opportunities here.

Intern at the Arboretum

We are currently recruiting Fall Site Interns!

Applications are due September 18th. Learn more about the opportunity and apply or share it with people you know.

Donielson Fund

As we move from Summer to Fall, we are also shifting from the potential for fire to the potential for flooding and ice damage. What keeps us steady in the face of increasing seasonal events that overload and damage our site is the knowledge that we are poised to respond, and have the support to do so. The Dave Donielson Natural Emergency Recovery Fund of the Arboretum is for just that - providing the necessary support for our recovery from these certain events. Help protect and care for the Arboretum through all circumstances by supporting this Fund today. 

Fire Season Continues

Don't smoke, use barbecues or fireworks, or make fires.

Thank you for keeping the Arboretum safe all year long.

In-Kind Wishlist

Straw Bales

We reuse straw bales year after year for our festival seating and many of our trusty bales have worn out. Contact us if you have spare straw bales and we can let you know where to drop them off. If you anticipate having extra straw bales in the future, please let us know.

Plastic Patio Chairs

Our supply of patio chairs for our festival booths is running low. Drop off used patio chairs at the Arboretum office.

Loppers

We are in need of additional loppers for vegetation management work parties. Drop off new or used loppers to the Arboretum office.

Recumbent Bike or Tractor Seats

Next Mushroom Festival will feature a pedal-powered cider press and we need seats for it! Drop off seats from tractors or recumbent bikes at the Arboretum office. 

Red Milkweed Beetle

"On a recent insect walk at Mount Pisgah, I was all eyes when someone spotted this red-spotted beetle. So was the beetle — it has four of them, a trait that’s reflected in the genus of its scientific name: Tetraopes femoratus..."

Read more about red milkweed beetles in a recent blog post by Karen Richards.