Ciderfest 12!


It’s the most wonderful time of the year! The air is sticky and sweet with appples clinging on the tree. People are smilling at you more. Even your dog has a look of wonder in his eye. ITS CIDERFEST TIME, YALL.

So come on down to Cidertown (aka Angel’s house in Adair Park) on Saturday, October 8th from 11am-ish till dark to get your belly full of cider and your heart full of Fun, Fall, and Friendship.

We’ll have trucks full of apples, bike and hand cranked presses, live music from Uncle Daddy and the Kissin Cousins and others, a screen printing station, trampolines, dogs, and antics!


  • Bring your cider mug to Cidertown
  • If you or someone you know would be interested in playing at Ciderfest, reach out to [email protected]
  • We are looking for Ciderfest t-shirt designs for the screenprinting station! If you would like to take a stab at one, please remember it is being hand printed, so no fine lines or small details. There are some examples below. Please email your design to [email protected]

New fruit tree map!

Map Screenshot
We have a new fruit tree map! It’s at the same URL as the old one: It was made by Karl Kim of Carl DiSalvo’s Public Design Workshop at Georgia Tech. If you are hiring programmers, you should hire Karl because he’s really pleasant to work with, he’s dedicated and he’s hard-working. And he’s got a freaking CS degree from Georgia Tech. What more do you need?

Anyways, our new map has a much-needed interface update. It now takes up the whole screen and has a dedicated sidebar for tree information, so you have plenty of room to see the map and tree information at the same time. You can also now search by address, latitude/longitude, or tree id.

The map also now has features for our Tree Parent program. Do you pass by a fruit tree in your neighborhood or on your way to work? Adopt the tree and send us an occasional photo of the tree during fruit season — you’ll be helping us tremendously by letting us know what’s up with the tree and when it’s ready to be picked. You can upload a photo of the tree and rate its pickability directly through the map.

Our new map has lots of behind the scenes features to help us get a handle on organizing our years of picking data. With almost 3000 trees in our database, it can be hard to plan events and keep track of what is ripe, so our new map brings all of our picking and donation data under one roof, and we now have scheduling features to help remind us when to check on certain trees. This is not as directly useful for non-CJ folks, but it helps us plan more events!

Upcoming Trees

This also means that you can now inspect our data on a really granular basis and see when we picked a tree, where we donated it to, when someone rated the tree or when someone uploaded a photo of the tree:

Pear Tree Graph

So check it out, find something tasty, let us know about any bugs, and send us your tree photos!

Concrete Jungle’s fruit tree sensors

One of the biggest challenges we face in running and growing Concrete Jungle is planning around the varying schedules of the thousands of fruit trees in the Atlanta area. Some trees will produce early, some produce late, some not at all. Some produce on-schedule but drop their fruit earlier than expected, some produce a bumper crop and should be prioritized, etc.

This is a problem that varies with the type of fruit. Serviceberries in Atlanta were planted almost entirely by Trees Atlanta and the few varieties they’ve planted are quite predictable: we are pretty much guaranteed to be picking serviceberries on May 23rd no matter what. Apples and pears, which are more diverse in variety and make up the bulk of our picking weight, are much less consistent.

Because it’s difficult to know what a tree is doing in a given year, we often simply have to physically inspect a tree. This means we spend a tremendous amount of time wandering around Atlanta, checking on our vast, sparse, urban orchard week-after-week.

Design for foraging

For the past two years or so, Concrete Jungle has partnered with Carl DiSalvo’s lab at Georgia Tech’s school of Digital Media to get a handle on this. Primarily we’ve been trying to develop ways to remotely sense fruit growing on trees. Before we get in to those ways, let’s discuss the partnership some. Why would we want to work with Carl, and why would Carl want to work with us?

Carl’s group focuses on design research, which is exactly what it sounds like: studying how things might be designed. It’s several steps up the chain from actual manufacturing of any physical article. At the design research phase, we have an end goal in mind that we wish to realize but there are several different avenues that could get us to a solution. This is great for us: we know what problem we have and aren’t too picky about how we get there. For a long time we thought of Carl as our crazy ideas outlet and, to a design researcher, a crazy idea starts the conversation. Maybe there is a feasible alternative to the crazy idea. Or maybe the technology to make the crazy idea a reality is just around the corner. Or maybe the crazy idea is really simple if you approach the problem from this direction…

Carl’s group likes us because they already have a heavy focus on food systems, infrastructure and maps, so a local non-profit that maps fruit trees for foraging and donation is a perfect fit.

Now that we’re working together, how do we actually sense fruit growing in a tree?


Our first approach was to use drones. The apple-pie-in-the-sky idea was to have a drone fly to a fruit tree, take a photo of the tree and return. Also don’t hit any trees, animals, cars or power lines. And don’t freak anyone out, so maybe fly only at night. We’re in fantasyland at this point so the drone may as well also pick some fruit and bring it back for us to sample.

Drone edge detection

Our drone camera detecting the outline of an apple in the foreground


We did some preliminary work and started to develop computer-vision software that could identify fruit growing on fruit trees. But this was the apple-pie-in-the-sky idea because it was basically impossible, both because 2014 consumer drone technology wasn’t capable, but because it was legally impossible as well. The FAA had a variety of strange and onerous drone rules in place at the time, requiring flight manifestos, trained drone operators and trained drone spotters for each flight. Carl received an email from the Georgia Tech Associate Dean of Research informing him that “policy of the FAA is that if a FAA-sanctioned institution is caught breaking FAA rules, then the entire institution can have their regulation revoked.”

So that shelved the drone project for a while…what other sensing options did we have?

Ethylene gas sensing

Sensorsense box


Fruits that are climacteric are fruits that ripen in the presence of ethylene gas. These are fruits like apples, bananas, tomatoes, and melons, and this is the reason people suggest putting some fruits in a paper bag with a banana to encourage the fruit to ripen.

Ethylene sensing would be ideal since we’re directly measuring a gas produced in response to fruit ripening. Ethylene concentration passes some threshold, sensor tweets at us and we go pick it. Easy as.

The problem is that the only ethylene sensors on the market are large units for commercial fruit storage warehouses that are parts-per-billion accurate and likely thousands of dollars per sensor setup (you know you’re in trouble when you see “request a quote” instead of a price.)

There is a company spun out of MIT named C2Sense that has some promising new carbon nanotube-based sensor technology that promises ethylene sensors for pennies apiece. The basic principle of the sensor is that you attach an ethylene-sensitive molecule on to a carbon nanotube, hook up two electrodes to the nanotube(s), and when ethylene is present you can measure some electrical change. Unfortunately, like most companies using carbon nanotubes, they are shipping neither product nor prototype.

(side note about those C2Sense sensors: they used a really cool process to make early versions in the lab. First the carbon nanotubes are functionalized, whereby some the ethylene-sensitive molecule is attached to the nanotube. That’s pretty normal. Making the electrode connection is a bit more difficult, and they developed a neat solution: they took their functionalized nanotubes, compressed them in to a small rod, and put that rod in a standard mechanical pencil. Making the connection between electrodes is then as simple as drawing a line with the pencil.)

Electronic nose

Electronic nose

(from “Detecting cooking state with gas sensors during dry cooking”, Ubicomp 2013)

There’s lots of cheap gas sensors out there based on tin oxide semiconductors. Although they are often sold as an alcohol sensor, methane sensor or hydrogen sensor, these sensors can be responsive to a variety of gases beyond what their label indicates, and there are a variety of powerful data analysis methods out there to tease out additional information.

Mechanical sensors

One way that you can tell a pear tree is ready to be picked is simply by how it looks. Its long, thin branches, normally upright, are bent over, laden with heavy fruit. So perhaps we can sense branch bend angle and use that as a proxy for fruit ripeness.

This approach is the most tenuous for producing good data (since branches will constantly be bending and swaying with weather and disturbances), but that can probably accounted for and having a cheap starter sensor will let us develop the rest of the sensor platform so that when an appropriate sensor is available we can drop it in and go.

Human sensors

Tree tag

If we can get passersby to send us photos of a fruit tree, then perhaps that will work out just as well as us visiting the tree in person.

These tie in nicely with Concrete Jungle’s Tree Parent program, where we encourage residents to adopt a local fruit tree and check up on it occasionally, letting us know when it’s nearing readiness. Plus we get some good marketing and educational value out of them.

Embedded tree camera

As unglamorous and straightforward as this is, a camera would show us exactly what we want, and we simply have to solve for the infrastructure around it, mostly being communication and power. On a large enough scale, we might have to develop image processing capabilities.

Any other wacky idea

I’ll just leave this here:

CROPS apple pinger

(from the 2013 workshop)

So how are we progressing? Stay tuned for part 2…

Learn How To Scout Apple Trees!

Ever wanted to learn how to find apple trees on your own?  Check out this amazing video our friends Ethan Payne and Jimmy Rowalt made to help you scout and pick apple trees!  Let us know what you find!


We made it!

Thank you sooo soo much everyone! We made our crowdfunding goal of $11,000 ($11,045 to be exact), had an amazing fundraiser hosted by the generous folks at Ladybird, and are on fire for fruit!

In lieu of us jumping for joy, here’s a great picture from the Ladybird fundraiser:

jumpy balls

Stay tuned!

Fruit is here!

Nanking cherries near Freedom Park

Nanking cherries near Freedom Park

It’s the best time of year! The season is fresh, the weather is great, and all variety of flower smells are on the air. Serviceberries are starting to peek out and the characteristic purple stain of mulberries is showing up on roadways and sidewalks all over the city.

We’ve got our first two picks of the season coming up: this Sunday at 11am at Centennial Park in downtown Atlanta, and a weekday next week (TBD) at Freedom Park. Please come on out and join us! Both locations are family-friendly and easily accessed by bike or public transportation.

Hunger Seder ATL – April 9

Register here and visit our #HungerSederATL site to learn more.

Pack it up, pack it in…

We got a new shed!! Come and check it out tomorrow at Doghead Farm 10am-12pm and help us harvest the veggies that have survived the cold.

Fun in the Sun!

Feeling cold and wet on this dreary day?  Good news!  Saturday, January 17 promises a high of 60 degrees and sunshine all day.  What better way to spend a warm-ish, beautiful winter day than at Dog Head Farm?!

Saturday, January 17–10am
Dog Head Farm
1117 Birch St SW
Atlanta, GA 30310


Greetings folks, happy fruit year to ya.  And wow….holy winter!, hope y’all have been protecting your sensitive plants….

We wanted to start out the year saying thanks to all our volunteers, do-gooder folks, and supporters. Scrolling below reveals a fun and busy year shaking trees, gulping cider, and improving soil. Go ahead, re-live the glory with CJ with just a flick of the mouse……

January means a few things to us:

It’s planting season! and Concrete Jungle commands you to plant!

Secondly, where to get all these delicious edible plants??  The ALFI fruit tree sale is January 24th at the Georgia Organics office. Stop by our table and talk fruit with us. Both fruit trees and ‘money tree’ donations will be accepted for our projects.  Thanks for your support enabling CJ to promote fun and intriguing ways to provide fresh produce to those who need it.
Check it out the ALFI fruit tree sale catalog,

Also at Dog Head Farm, the next farm day is Jan 17th. More info on that soon.
Also, also….Believe it or not, get your fruit goggles out already….Yes, the Prunes mume is in bloom right now. Just a reminder to stay watchful Atl…..and food is everywhere!

See you soon.

Support Concrete Jungle!

Upcoming Events

In season/upcoming foods:
  • Apples
  • Muscadines
  • Pears
  • Persimmon
  • Flying Dragon
  • Okra
  • Pomegranates
  • Watermelon
  • Quince