In a few short weeks the AAFC bakeapple team will be back in Makkovik to start another season of field research. While the berries are still three months away, June is an important time in the life of an appik.
Bakeapples form flower buds in the late summer, nestled close to the rhizomes (underground stems) under the surface. They mature slowly over the winter. When the ground starts to warm up in the spring, they’re ready to poke their heads up at last and grow towards the sun.
When the flowers open, we’ll finally learn something they’ve known since the buds formed last year: whether they’re a boy or a girl! Most plants have male and female reproductive structures together in the same flower, or in some cases in different flowers on the same plant. Bakeapples have separate male and female plants, and all the flowers on a plant will be the same sex.
That might sound strange, because bakeapples only have one flower on a stem. But what we don’t see above ground is that each of those tiny stems is attached to an underground rhizome (a horizontal stem just beneath the surface), and that can spread for ten meters or more. Making each individual bakeapple stem just one branch on an underground bakeapple “tree”.
Male flowers have a ring of yellow stamens inside the petals. They seem to emerge a day or so before the females arrive, and also stick around a little longer after the females have gone. They attract insects with a combination of sweet nectar, secreted from the center of the flower; and pollen, released from the anthers at the top of the stamens. As the flies travel from flower to flower, they transfer (hopefully!) some of the pollen to female flowers, effecting pollination.
The stamens of female flowers don’t develop fully. Instead, they have a cluster of green pistils in the center of the flower, each topped with a stigma. The stigmas are in just the right spot to scrape pollen grains off the bodies of visiting flies. If that happens, the pollen grain will germinate, growing through the ovary and fertilizing the ovule (egg) at the base. The fertilized ovule will then release hormones that tell the plant it’s ready to make a fruit. If all goes well, 4-6 weeks later we’ll have a delicious appik to pick.
If the flowers bloom too early, or there is a late cold snap, they may be damaged or destroyed by frost. This doesn’t cause a lot of damage to the plants, but it will prevent the flower from producing a fruit this year.
When the weather cooperates, and the flies do their job as pollinators, the fertilized bakeapple starts developing a fruit. The first signs are the white petals dropping, and then the green sepals close up around the ovaries. This provides a safe space for the fruit to develop.
With all this activity going on, is it any wonder we botanists are keen to be there in person to see it for ourselves? 2025 will be our fourth year studying Makkovik bakeapples. We will be collecting a variety of data on different aspects of bakeapple biology:
- Flower tagging: we use metal tags to mark individual plants. This allows us to quantify how many flowers survive to produce fruit each year.
- Flower transects: we have set stakes to mark out 10 meter “transects” that we return to each year. We’ll count all the male and female flowers on the transect, including how many of the females have been damaged by frost or insects. When we return in August we’ll count again, to see how many fruits were produced along each transect.
- Time-lapse cameras: we have a set of (mostly) weather-proof cameras that we train on freshly opened flowers. They are set to take a photo every 10 minutes during the flowering season, and then every hour until the fruit ripens. This gives us more information about the timing of flowering, and how long it takes for a berry to ripen.
- Temperature loggers: at each of our transects we have air and soil temperature loggers. We’ll use the data from these instruments to better understand how temperature influences when the flowers emerge, how long it takes to produce a fruit, and how extreme heat and cold impact the plants. At least, that’s what we’re planning to do. We’ve had some challenges with this equipment. The foxes on the southard islands take great delight in digging them up and chewing them to pieces!
- DNA sampling: we’ve collected leaf samples from some of the sites, and plan to complete the rest of the sites this year. We extract DNA from the leaf samples, and do a kind of “fingerprint” analysis. This allows us to determine how many individual plants are present at each site, and how closely they are related to each other.
- Flower netting: new this year, we will be putting mesh bags on some of the bakeapple flowers. This will prevent insects from pollinating the flowers, so we can better understand how the plants respond to pollination.
- Nutrient sampling: also new this year, we will be collecting leaf and soil samples, in order to better understand how the sites differ in terms of soil quality, and to identify which nutrients the plants may be lacking.
Keeping track of all of that will keep us very busy in June! We really appreciate how respectful everyone has been (except for the foxes). Thank you all for leaving our equipment where it needs to be to do its work. And please don’t hesitate to enjoy the bakeapples like you always do. We made tried to design our experiments so that we wouldn’t get in anyone else’s way, and we know you’ll be out collecting berries in August. We’ll be back to collect more data then too, and you can be sure we’ll be picking a few berries ourselves when we do.