stratigrafia

Moon over cliff

by Steven Holland

Thoughts on programming, science, nature, and growth through willful change. Oh, and pop-tarts.

GO TO ARCHIVE

Subscribe to RSS Feed

Brown Bellytooth

24 April 2021

After a good hard rain, a snail search turned up the usual suspects on our street, with about four Common Buttons for every White-lipped Globe. Searching the leaf litter around one of our hickories revealed an empty shell of a species I haven’t found before, a Brown Bellytooth.

Read more...

Two common snails

18 April 2021

With spring, snails are becoming more active, and you can easily find them on our street the morning after it rains. Two of these are common to the region, the Common Button and White-lip Globe. I have found a third snail in our neighborhood, but have seen it only once. I will post photos of it when I have more photographs and a better description.

Read more...

Converting an app from UIKit to SwiftUI

21 February 2021

UIKit apps and SwiftUI apps have a completely different internal structure in Xcode. Building on Sam Khawase’s great guide, here is how I have converted my apps from UIKit to SwiftUI. My conversion is done in one step, instead of progressing through a series of steps where the app is a hybrid of UIKit and SwiftUI.

Read more...

Minimal MVVM in SwiftUI

20 February 2021

Using SwiftUI effectively is made easier by choosing the right architecture for your app. Ever since Cocoa, Apple had emphasized a Model-View-Controller (MVC) architecture, but SwiftUI works best with a Model-View-ViewModel (MVVM) architecture.

Read more...

Currahee flowers — October

1 November 2020

Even so late in the season, Currahee Mountain still has flowers, although most of the fall within a single genus of asters, Symphyotrichum. Many of the flowers are smaller, and there are fewer of them, so they aren’t as noticeable as the explosions of color in May and September. Even so, a few patches of blue asters are quite striking.

Read more...

An Unappetizing Milkcap

11 October 2020

On our walk this morning, Tish noticed a particularly unappetizing mushroom, and we both commented that it looked like entrails. It’s one of the Milkcaps, called the Silver-Blue Milky, or Lactarius paradoxus.

Read more...

From CocoaPods to the Swift Package Manager

4 October 2020

For several of my iOS apps that needed Dropbox capabilities, I’ve used CocoaPods to let me use the SwiftyDropbox framework. CocoaPods offered a great way to incorporate external frameworks, but I wasn’t a big fan. Updates were done by the command-line, and every new Swift release made the whole thing seem fragile. When I saw that SwiftyDropbox was now available in the Swift Package Manager, I knew it was time to switch.

Read more...

Currahee flowers — September

27 September 2020

Just as in Athens, the trail up Currahee Mountain is covered with yellow flowers. What surprised me, though, was the amazing diversity, as well as the number of less obvious flowers that are not white.

Read more...

September Wildflowers

20 September 2020

September is the month of tall plants covered with yellow flowers. There’s also a few that are less common, less obvious, and take a little searching. These are the flowers of September.

Read more...

Brown Snake

13 September 2020

Brown Snakes (Storeria dekayi) are a very common snake in this part of Georgia, but often go unnoticed because they spend much of their time under the leaf litter. I saw this one on our street one morning in late May.

Read more...

August Wildflowers

12 September 2020

Why yes, it is the middle of September. What better time to tell you what flowers you were looking at a month ago, in August? Both the diversity and especially the abundance of flowers was way down in August, maybe because it had been so dry. Here are the new flowers of August.

Read more...

Swift and Raspberry Pi — an update

7 September 2020

Several years ago, I wrote a series of posts on running Swift on a Raspberry Pi and using it to interact with sensors. Several changes have been made to Swift and it’s time to bring that work up to date.

Read more...

The Return of the Fungi

30 August 2020

After a rainy week following a hot and dry summer, fungi have exploded in our forests. On a hike in the UGA Botanical Gardens this week, I’ve never seen so many or so many types before. Here are some photographs of those, plus some from our yard, and some from Currahee Mountain.

Read more...

Timber Rattlesnake

29 August 2020

Timber Rattlesnakes (Crotalus horridus) are widespread and common in the eastern United States, but I’ve rarely seen one (maybe twice before in 50 years). Seeing one is a real treat, especially when it as beautiful and large as this one from Currahee Mountain.

Read more...

July Wildflowers

1 August 2020

Summer brings its own flowers, many who have been greening up since winter. A few earlier bloomers are still going as well, including Mock Strawberry, Cat’s Ear, White Clover, Carolina Horsenettle, Smooth Spiderwort, and Rough Daisy Fleabane. Here are the new flowers of July.

Read more...

A Few More Fungi

31 July 2020

Some hiking in the UGA Botanical Gardens a couple of weeks ago revealed several new fungi, a few of which I cannot identify.

Read more...

A Few Fungi

28 June 2020

Learning fungi seems daunting, but even so, it’s hard not to notice some of the more obvious ones. Here are a few from this spring. Some are from our neighborhood, and many are from the UGA Botanical Gardens. Luckily, Mary Woehrel and William Light have written a great book specifically on the fungi of the area, Mushrooms of the Georgia Piedmont & Southern Appalachians.

Read more...

June Wildflowers

23 June 2020

Even though the abundance and diversity of flowers have really tailed off from April and May, some new flowers have appeared. These are the flowers of June in Athens.

Read more...

Currahee Wildflowers, Part 2

21 June 2020

I returned to Currahee Mountain yesterday to figure out yellow flowers. I also found a few new ones.

Read more...

Currahee Wildflowers

13 June 2020

A hike to the top of Currahee Mountain last Sunday surprised me with an extraordinary diversity of flowers. The flowers showed well the relationship between soils developed on felsic versus mafic rock, as well as the difference in flowers between forests and more sunlit areas.

Read more...

Dragonfly Bookends

7 June 2020

My adventures today started and ended with unusual dragonflies: a Fawn Darner and a Gray Petaltail.

Read more...

Oak-Apple Galls

6 June 2020

All spring, I’ve noticed brown lumpy spheres about the size of a golfball, and figured they were a puffball, a type of fungus. They’re not; they’re much more interesting.

Read more...

Trees of Athens: Shrubs

28 May 2020

We have several types of shrubs, both native and introduced. This list is likely to grow, as I am certain I have only scratched the surface of what is around.

Read more...

Trees of Athens: Simple Toothed Leaves

27 May 2020

We have at least ten common local trees with simple toothed leaves, and they can be difficult to tell apart. For many of these, the bark is often the best clue for identification.

Read more...

Trees of Athens: Simple Entire Leaves

26 May 2020

We have five common local trees with simple, non-palmate leaves that have smooth (non-toothed) margins: Black Tupelo, Flowering Dogwood, Osage Orange, Southern Magnolia, plus the non-native and highly invasive Chinese Privet. All of their leaves are distinctive.

Read more...

Trees of Athens: Palmate Leaves

25 May 2020

The leaves of all of these trees have veins that radiate from the base of the leaf. In the Athens area, these include four maples (Red, Florida, Chalk, and Boxelder), the Sweetgum, American Sycamore, Tuliptree, Sassafras, Eastern Redbud, and the non-native Royal Paulownia.

Read more...

Trees of Athens: Oaks

24 May 2020

Oaks are abundant and diverse in our neighborhood. Although they are generally divided into two broad groups, the white-oak group and the red-oak group, I divide them here into oaks that have leaves with rounded lobes and those with pointed lobes.

Read more...

Trees of Athens: Compound Leaves

23 May 2020

All of these trees have compound leaves—multiple leaflets as part of a single leaf. There are those that have relatively few leaflets, the hickories and the ashes, and then there are the hypercompound trees that have zillions of leaflets. There’s also the Winged Sumac, which can’t decide if it is a shrub or a tree.

Read more...

May Wildflowers

22 May 2020

April’s flowers have given way to a largely different set of flowers. Rural roadsides in Georgia are spectacular this time of year.

Read more...

Hatchling Box Turtle

17 May 2020

This little guy showed up in our lawn while I was mowing today. It’s a hatchling Box Turtle.

Read more...

Trees of Athens: Conifers

16 May 2020

We have four common native species of conifers in the Athens area. Three are pines (Loblolly, Shortleaf, and Virginia), plus the Eastern Redcedar, all of which are evergreen.

Read more...

Trees of Athens: An Overview

9 May 2020

Last summer, I started to learn the trees of our neighborhood and Athens in general. I’m now able to start writing my notes on how I learned to identify them.

Read more...

Copperhead

5 May 2020

Copperheads are common snakes in the southeastern United States, but it is not often you get a good of a view as this one.

Read more...

Neighborhood Ferns

2 May 2020

Ferns are common in our neighborhood, but not very diverse. Of the five species, only one is particularly common and widespread.

Read more...

A Sunday-morning Paddle

26 April 2020

Bright blue skies and comfy temperatures make it a perfect time for a paddle down the North Oconee.

Read more...

Neighborhood Vines

25 April 2020

Next up on learning the neighborhood plants: vines.

Read more...

Neighborhood Wildflowers

20 April 2020

With spending more of my walking time in the neighborhood, I’ve noticed how many spring wildflowers we have nearby.

Read more...

Mystery of the Spikes

19 April 2020

Odd-looking wooden spikes began showing up on our sidewalk. The mystery was soon solved.

Read more...

Spring Caterpillars

18 April 2020

Although late summer and fall is usually the bonanza time for caterpillars here in the Piedmont, I’ve seen many caterpillars the past two weeks. Both are species of tent caterpillars.

Read more...

Little Brown Skink

17 April 2020

After over twenty years in this house, I am still finding new animals. Today it was a Little Brown Skink (Scincella lateralis).

Read more...

Really deleting zoom

2 April 2020

There’s deleting Zoom, and then there’s really deleting Zoom. Here’s how to really scrub away all traces of it.

Read more...

Spring wildflowers, part 3

27 March 2020

The day after the rains was a great one for flowers, including a couple of new ones.

Read more...

Doubling time to 10x time

26 March 2020

Many of the recent articles on COVID-19 talk about the doubling time of the number of cases, but I wanted to think about it in terms of order of magnitude. The conversion is straightforward.

Read more...

Spring wildflowers, part 2

25 March 2020

A rainy-day hike in the UGA State Botanical Garden showed that most of the flowers were closed up, but there was one nice new one: a trillium.

Read more...

Subclassing NSManagedObject

21 March 2020

On a recent CoreData app I was building, I subclassed my NSManagedObject, but ran into a couple of snags. Here’s what happened, how I fixed it, and how I could have avoided them to begin with.

Read more...

Spring wildflowers

20 March 2020

A hike in the UGA State Botanical Gardens showed sure signs of springs: lots of wildflowers, and a surprise.

Read more...

Look for the gift

19 March 2020

Right now, it can seem like the wheels are flying off the cart. But one of my favorite teachers of our children, Maggie Hunter at Athens Montessori School, offers the best advice I’ve seen.

Read more...