Strawberry Pollinator Diversity, Significance, and Management

- I'm gonna be talking a little bit about strawberry production itself.

Some of the pollinators that you would encounter and then a little bit about management practices and how that shapes both your pollinator community as well as your strawberry yield.

So my name is Jeremy Slone.

I'm actually a co-advised by Margarita as well as another advisor, Hannah Burrack down at NC State University and most of my work is done in the Carolinas but you guys actually use a lot of the same varieties and similar production practices.

So strawberries require complete pollination in order to develop into like larger, more symmetrical fruits.

Complete pollination simply means that the more receptive center part of the flower requires a single pollination events and each event turns into what we think of as the seeds on the outside of a berry.

So rather than seeds, those are actually the berry itself, they're called achenes.

Now, strawberry plants are a little complicated but most of the root mass is going to occur in about the top six inches of soil, kind of come together into a little crown region and that crown region is what gives rise to all the different shoots.

So you'll get your leaves, your bloom clusters and also runners that will generate daughter plants.

So that's generally how strawberries are propagated is through these daughter plants.

You could grow a plant from one of those achenes but it's not going to be true to type.

Now on each of the bloom clusters, you can get different sized berries and it's based on where it occurs on the stem.

So if you follow this stem all the way to the end, you get your primary fruit.

That's gonna be your largest fruit that's gonna occur on that particular stem.

The first branch off from there is your secondary fruit and then anything that comes after that they're going to be significantly smaller than the other one.

So you're getting a matrix of different fruit sizes from each individual bloom cluster and the flowers are gonna be correspondingly sized the same way.

So strawberry plants once they go into the ground can produce fruit for several years.

However, you start to get a little less each year.

To kind of like maximize output, most of the time they're grown annually.

You put them in the ground in the fall, they kind of overwinter, accumulate some root mass and then they're gonna be blooming in that spring period, in which case they're ripped out and then replant it again.

You can imagine that is an incredibly high production cost because you're laying these plastics down, buying plant plugs every time.

However you're maximizing your yield and you're also dealing with shorter rotations and can move this field around which tremendously helps with pest pressure.

In Pennsylvania, you do see more matted row.

You would plant your plants in the spring, pick off the blooms, kind of let the canopy build up and let those runners kind of branch out and fill in essentially a matted row.

And once you have these plants established, you could let them then fruit for several years, you might get several flushes of fruit per year.

So you do have some advantages to this but as you can imagine, after a year or two, you may have different pest pressures, both insect and fungus but also you're gonna have a significantly less production cost going in.

So they're kind of pros and cons to each but you're only gonna use different varieties because a lot of the annual crops are grown from June bearing, so they're gonna only fruit for that one time during the year.

But then you have some ever-bearing varieties that are used for matted rows that again may produce flushes of fruit throughout several times during the year.

Something else you do see fairly frequently is high tunnel and greenhouse production, which basically just allows you to grow these fruit outside of normal production times.

Both of these are high tunnels and the one on the bottom is one that occurs in the winter from North Carolina.

These open sides kind of allow for sufficient airflow for pollination and also they're just kept warm by the tunnel to the point that we can have fresh fruit year round if we wanted to.

Now the other one is a pigs in Brazil, they have these elevated tables, which makes harvesting significantly easier but also rather than using soil, they have these bags that are essentially like a corn husk fiber, they put their plants directly into that bag and rather than having to rework the soil, they can toss that bag out, throw a new bag down and kind of keep going.

So you've got different options in terms of production but a lot of these are gonna be sort of contextual to the variety and the needs of that particular variety may have.

The strawberries do require complete pollination.

Each of those achenes that develops on the outside of the fruit was a pollination event.

So you can imagine the receptive female part of the flower in pink has to get pollen from either that male region which is in blue or from another flower and when you don't have this happen, what happens is those achenes never form and the fleshy part of the fruit that we like to eat, the red part, only swells up where those achenes are present.

So when you see these really odd-shaped berries, sometimes that's a flower problem.

Oftentimes it's a pollination problem and it is pretty easy to tell the difference but you do have several vectors of getting pollen around between flowers.

So obviously these flowers are self fertile.

It's important to note that not every variety is as amenable to self fertilization.

Some it doesn't matter, some it's actually such a low-quality pollination being selfed that it doesn't really generate much of a fruit at all.

So in some cases, varieties are gonna really heavily rely on this wind borne or insect mediated pollination to get the pollen between flowers, essentially, to make it a higher quality.

So this is a study I believe that was done in the UK and they were looking at a couple different pollination treatments.

If you backup a flower and only let it pollinate itself, for some varieties, you're gonna get these really crazy shapes, they won't form at all.

They're unmarketable.

Now if you have open pollination that's gonna allow wind and insects to kind of vector pollen around.

And again, there will be some self fertilization but also it's moving around between flowers and you can get a pretty good berry.

Now hand pollination is where you take a paintbrush and you absolutely saturate a flower.

It's not gonna get any more pollen than that.

So you can see it in an open pollinated system can actually get quite close to that.

So at some point, you're not really getting a benefit from having more pollen, you just need to reach that particular point where it's sufficiently gonna generate a good fruit.

Now, this was another study that looked at it and what you got here is fruit weight and commercial grade.

Again based on a couple treatments, self pollination, wind only and then also insects mediated.

Each of these gray lines represents a different variety.

So you can see that some varieties are absolutely just not gonna generate a fruit from self fertilization but others actually can be quite high and even better than some fruits that have insect mediated.

So it's important to remember the varieties are quite variable but if you average it out here with that red line, you can see again having insects is typically gonna provide you some incredible benefits in terms of generating larger more symmetrical fruit.

So fruit way it's going to be higher but also grade.

So the commercial grade of these fruits is grade one, which is the highest is for bee pollinated.

Nonmarketable fruits do still occur because they're simply not gonna ensure every flower is perfectly pollinated but in a case where you only have self pollination, you're gonna get mostly nonmarketable fruits.

If you were trying to produce these for some kind of a profit, you really do need insects on your farm for the most part to actually generate fruit that's gonna be usable.

Say for example, if you're doing like annual production with these high production costs.

If you're not able to return that it can actually be really devastating ultimately for a long-term plan.

But you can imagine here that strawberries are an early season crop generally.

So they're blooming when it's still cold outside, there's a lot of reduced insect activity and generally a lot of these native bees haven't really emerged yet.

So a lot of growers are out to rent honey bees.

They do tend to pollinate strawberry flowers.

Something like a bumblebee shows very little interest in strawberry flowers.

Interestingly, in Japan, they actually use Syrphid flies.

They master them for survey pollination.

So there's a lot of different options but a lot of growers in our region are gonna rely on honey bees.

It's unclear how many honey bees you need per acre, there are recommendations from half of a hive per acre all the way up to four hives per acre.

But again, I think part of that is because nobody's really assessed those differences between varieties sufficiently and it's also gonna be somewhat regionally specific.

But honey bees come with a tremendous foraging force.

In a small amount of are, you can have a ton of pollinators and most strawberry farms are fairly small.

Not a lot of the times are these gonna be very large operations and in those cases, wind borne pollination is gonna be a lot more effective simply because you've got more area devoted to it.

When it comes to native species, overwhelmingly what we encounter are Lasioglossum which are those small kind of metallic black bees.

These are Ground nesters, they're solitary species but what you'll find is that they're just simply are not nearly as abundant as those honey bees are.

So even though you may have some sites where these are particularly abundant, there will be sites where there's only a handful of them there.

So while they're generally the most abundant pollinator we have, they can't be the only one that we may be relying on.

The next most common I believe is the Andrena, So the one we saw the most was a big Andrea and a Sonia, a slightly larger black bee, a lot hairier.

We've also got the Augochlorella green bees, which are similar in size and shape to the Lasioglossum but they're gonna be bright green so they're easy to kind of see on the wing and then also this Halictus ligatus.

They look a lot like an Andrena but they have these really interesting shovel shapes on their head.

Over a two-year sampling period across a bunch of different sites, we collected about 12 different bee genera and as strawberries are blooming for about a two-month period.

So there's a long time where bees may be present and different ones will emerge over time but in general, we didn't see a ton of diversity.

There were about six or so groups that were really predominant and then a handful of rare species that likely weren't contributing a whole lot to pollination but were there to kind of help carry it along and maybe you're gonna have higher populations in different years.

Again, overwhelmingly what we saw the most of was Lasioglossum.

We ended up seeing we had about 13 different groups of Lasioglossum.

Sometimes these species are so hard to tell apart and what we ended up seeing is that there were 12 genera but only about 13 species of Lasioglossum and this was kind of across the Carolinas.

Now let's look at the non bee insects but really what I wanna stress here is there's a lot of insects in the field and a flower that happens to be self fertile.

You really kind of just need to walk across the flower to help with pollination.

So really anything that's looking for a pollen or nectar reward, whether it be a protein or sugary substances, visiting a flower is all it takes.

So Syrphid flies are what you see here in the center and that's the one that kind of is a bee mimic and you do see some butterflies but they're not nearly as abundant.

They don't stay in your field long but again, they're visiting flowers and that's contributing.

What I really find interesting is if you really pay attention, there are a lot of flies in most farms and you may not look pretty and you may not think of them as pollinators necessarily but honestly, they're incredibly abundant.

They visit flowers regularly and they're gonna be out, early in the season, when the weather's less ideal.

At times where bees simply aren't gonna be out and about but I think there's a lot of fly pollination that's occurring that people maybe aren't really appreciating to the full extent.

Now what about predators?

Syrphid flies as larvae are predatory on aphids.

Not only are they helping pollinate, they're also helping control your pests.

You've got things like Lady beetles and their larva, soldier beetles, different things that may be feeding on some of the pollen but ultimately, if they're amenable to that self fertilization all it takes is...

What about pests?

In some cases, they're gonna be feeding on pollen.

Things like the Lygus bug are very problematic 'cause they're gonna cause fruit damage and that's actually gonna make it unmarketable.

But something like the Clipper weevil or the Cucumber beetle might feed on the pedals, might feed on some pollen, maybe clip off one of your blooms but the plants are fully able to compensate for that damage, you can clip off several blooms on a strawberry plant, it'll just make more.

It's ultimately not gonna affect the yield but they may help to pollinate simply by again, walking across these flowers.

Different pest densities are gonna make a difference as to whether or not a pest is actually economically damaging or just kind of a nuisance.

Now, you might be wondering, why pollinator diversity is important?

Maybe if you have a handful of flies or a bee species, maybe that's enough but not necessarily especially in the case of strawberries, which again, are gonna be blooming for an extended period, both during the day as well as within a season.

So differences in foraging behavior are probably one of the biggest reasons why pollinator diversity is important.

honey bees like to land in the center of a flower and then they'll kind of move back and forth.

But ultimately, they're kind of pollinating what we think of as the tip of a strawberry flower.

They're not really getting down in there and kind of getting at the sides.

Whereas these smaller body native bees like to kind of get down in there between the anthers and actually climb around the outer edges.

So while they're both pollinating a flower, they're kind of complementing one another rather than ultimately competing.

So if you were to say only have honey bees, you may have fruit that don't develop properly at the crown.

Now, variable weather is another important thing.

Honey bees like to come out late in the day and they also do not like to come out when it's cloudy or rainy or cool but something like a fly or some of those native bee species don't seem to mind.

So in that case, if you have say inclement weather for about a week, that can be really devastating if your flowers are gonna bloom, open up and be receptive and then close before you really have a whole lot of going on.

So having a more diverse pollinator community makes you more resilient to differences in weather that may last for several days.

Also timing within the day and season.

When these initially start to bloom, the strawberry plants most native bees haven't emerged yet.

So we weren't seeing native bees until maybe our second or third visit to a lot of our sites but if you hadn't stocked honey bees, the only thing we were seeing is flies.

And again, if they're providing these important services, what's happening is that the flies are present really early and maybe dwindling off throughout the season.

So by the time they're dwindling off, you're starting to see this increase in native bees.

So you're complimenting each other both spatially on the flower but also temporally throughout the season.

Poor pollination, how can you tell that apart from say, other flower damage?

Here's an image on the left that I would most likely say was frost damage.

Probably what happened is the tip of that flower itself got damaged, just a cold night happened.

Whereas you can notice the berry on the other side has a very irregular seed set.

Some of the achenes didn't form at all and as I mentioned, when the achenes don't form, the red fleshy part of the berry doesn't swell up around it.

So you can tell that that one has very uniform seed structure and pretty uniform swelling but it's only in that one region where you've got clearly some kind of flower damage.

What does that one look like?

Anybody have a guess?

So it might have a little bit of frost to the end but notice that there are regions where the seeds haven't set, they're regions where somewhere larger than others.

A lot of that has to do with that one didn't get very good pollination.

So while it's swelling up right now, ultimately, that one's gonna take on a really contorted shape as it gets a little larger.

What about this? (audience laughing)

So this is just a flower anomaly.

Sometimes when the flowers form, it looks like two are connected or it's like a really weird shape.

You can notice that all the seeds are quite consistent, they're all fairly generally the same size.

So it wasn't a pollination problem.

This was just a weird fruit and it's not uncommon to see this.

Now that one very clearly is a pollination problem and you can see there's these crevices where clearly, there just was no pollination.

And again, it's gonna make a fruit but while you might be willing to eat it, if you were trying to market these that's gonna be much less desirable, especially if you have a you-pick operation where folks are coming to your farm to pick them their selves.

They're probably gonna pick like big, really pretty, symmetrical red ones.

That one's probably gonna get left there to rot and then potentially cause you bad fly problems.

Usually with Turner's plant bug, you're still gonna see seeds that are the same set, but you'll have that indentation that would look like poor pollination but without irregularity in the seeds.

And these were kind of fun ones, I thought for a minute that I had found a type of star berry and then maybe this was gonna be true to type fruit.

(audience laughing)

Turns out this was just a weird flower anomaly that happens at the beginning of the season.

I had about two or three farms where this happened but again, you can look at the seed set and see there's clearly no pollen limitation going on here and unfortunately, after about the first bloom or two those went away and they were really...

But this is just gonna be a fluke and not particularly problematic.

Again, based on what you're seeing about the actual seed set on the fruit itself.

So that's a little bit about strawberry production.

A lot of the work that I've done the past few years was trying to assess pests and pollinator management and kind of the integration of the two.

And in the case of strawberry farms, how to things like pesticide use or honey bee stocking rates and landscape context impact not only bee health but also your strawberry pollination.

And the reason we're interested in these three factors is because they're very variable practices.

You have both conventional and organic and within both of those management regimes maybe low or high intensity in regards to pesticide application number.

I have conventional folks that make no applications.

They just don't wanna get certified but I also have conventional folks that make 20 pesticides applications over a two-month period.

I've got organic growers that don't make any applications and some that make a handful.

We also wanted to look at landscape.

A lot of these smaller-bodied native bees simply don't have the energy to fly out for a kilometer distances like a honey bee can.

So within about a 500-meter radius of the farm is about the extent these little natives are gonna be able to fly.

Whereas honey bees again can fly much further.

So we took two different diameters around the farm, 500 meters and 1500 meters and we quantified land cover.

Whether a patch of land was in agricultural production, whether it was forested.

Again, if you're a you-pick operation, you might need to be located next to an urban area, what might that do?

And then natural is gonna entail say grasslands, shrubs, really anything that doesn't fit those other categories that might still be a suitable habitat for both food and nesting.

And then lastly, honey bee stocking rate.

People are kind of just doing this based on what they'd like to do.

So maybe you're an organic farm that wants to promote honey bees.

So you have five hives on your two acres of strawberries or you may just rent a hive from someone for a two-month period.

Tremendous variability in the approaches here.

And I work kind of across North Carolina but also dip down into Charleston, which we really had to twist my arm to do that but Charleston was really fun because they have similar production practices but it is a little warmer there and it's a lot closer to the coast.

And again, a lot of small farms, some located in the middle of a national forest, some located right on the coast.

Quite different from what I'm seeing, say in central North Carolina.

Now, what we did is we would visit farms several times throughout the bloom period say late March to at the latest early June and we would set out to different kinds of collection approaches here.

We would use pan traps, are a little fluorescently painted dishes with some soapy water.

So any insect that's flying around that happens to be attracted to that fluorescent color will fall in and then I can assess the general community that's going on there in terms of pollinators.

We also took sweet nets and we collect bees directly off flowers.

I know that that's a strawberry pollinator because it was on that flower.

Whereas anything I collected in the pan trap was simply in that field and maybe a strawberry pollinator but may not be.

So we were interested in assessing the whole pollinator community but also more specifically, just those that were gonna be visiting your strawberry flower and not say the clover growing on the side of your rose.

Now, in regards to pesticide intensity, I had a couple growers that I know are high-intensity growers, so they probably were spraying about 20 times.

They decided they didn't wanna give me their pesticide records.

So I feel like the effect of pesticides would be a little stronger here.

So we did see a decrease with increasing pesticide application number.

The majority of pesticide applications going out in strawberries are fungicides.

They might make an insecticide application, maybe a might a side application or so.

Generally no herbicides but a tremendous amount of fungicides and they're rotating modes of actions constantly.

So you're getting a variety of different chemistries out there at any given time.

The numbers here are gonna be representative of the magnitude of the effect.

So you can see that the magnitude of the effect of bee abundance being higher on conventional farms is a lot more intense than the deficit that occurs by an increasing pesticide application number.

Again, I bet that number in actuality is a little higher, which you also have a lot more variability here.

Plus something about conventional management actually favors an increase in bee abundance.

Maybe it's something to do with the diversification of crops they have, maybe it's some other non pesticide related function of their farm management but it was an interesting thing that we encountered.

Now, when it comes to landscape, you would assume that if you have a lot of natural land around your farm that must be great habitat, right?

Not necessarily, especially in the case of strawberries, which are blooming early in the season.

So we saw this interesting thing where bee abundance was lower when you had more natural land at this broad scale, which again, seems counterintuitive.

I think what's going on here is that you need to kind of get down to a finer scale.

So rather than simply saying, oh, there's natural land that's probably gonna be good for bees, you might need to know floral diversity, floral abundance, a little more about the availability of bare soil.

Again, if they're favoring this tilled soil, the amount of non compacted soil.

There's a lot of finer scale details about landscape composition that are likely gonna be driving this a lot more than simply land cover metrics alone.

We didn't see any effects of land cover metrics of say urban land or agricultural land which would suggest again that that's not the best necessarily at gauging what's gonna happen to your pollinator community as much as say, what kind of plants do you have other than the crop itself and how abundant are they?

Now, here was a fun thing we saw when it comes to honeybee stocking density.

We had differences whether we caught them with a pan trap or whether we caught them with a sweep net.

I want you to imagine that there are 10 flowers in a field and there are say, nine honey bees, and then maybe a handful of natives.

Those honey bees are gonna be at most of those flowers at any given time and if a native bee were to go to one of those flowers, they're gonna fly around and wait their turn 'cause most of the time bees don't wanna be on the same flower at the same time.

We saw a decrease in native bee abundance, as measured with the sweep net when honeybee abundance increased.

So imagine that that increased competition meant that those native bees were spending less time on flowers.

However, when I looked at pan trap data, having more honey bees looked like I had more native bees but again, if they were flying around more, they were probably more likely to encounter my pan trash and then get collected that way.

Ultimately, what this would suggest probably is that having extra honey bees means that everyone's flying around more because everyone's not wanting to interact on the same flowers.

There's just not enough flowers at any given moment to feed everybody.

Honey bees aren't necessarily increasing competition to the pollinator community as a whole.

So that's why it's important for us to analyze this data with different collection methods because we might have assumed that Oh, no, we're having this decrease in native bee abundance but it's likely driven by they're just being outcompeted at getting two flowers at the times that we were sampling.

Now this is just kind of showing you visits over time at the bottom and pollinator abundance on the side for flies and native bees.

The first visit, there's not a lot of variability.

But over time, you kind of get a general increase so that by the end, there's gonna be a lot more flies at any given site on average.

We saw the same trend with native bees but it took them a little longer to kind of get acclimated and by maybe the second or third visit that we made, which nears kind of the end of the season that's when you really start to see this increase in native bees.

So they're not really gonna be contributing heavily to your pollination because the flowers are gonna be gone by that point but what we saw in 2018 was a little different.

There were a ton of flies in the beginning and they kind of fizzled out over time but then our native bees did kind of a more drastic increase.

So a lot of this is gonna be driven by inter-year variability, differences in weather, at what point the soil warms up enough for these native bees to emerge.

Whether or not you happen to have flies that are coming through there.

Flies tend to not be central nesting foragers, so they're just kind of moving through your field.

But they're in such high numbers, that they're likely still providing that service at a time when honey bees are not or native bees.

So I'm gonna kind of move through the fly data, in contrast to native bees, which are likely gonna be impacted pretty heavily by pesticide practices didn't really seem to make a difference to flies.

Again, they're so abundant and transient within your field, they're likely not gonna get hit by the sprays and also, they're not really living there anyway.

In terms of conventional management it had these contrasting effects on abundance and diversity, conventional management may have some interesting benefits that we're not really assessing.

We saw kind of the same trend with greater natural land cover where it maybe decreased diversity but increased abundance.

And then same thing with 2018 diversity.

So there's a lot of these weird contrasting things that are going on and I think there's just a lot of things about flies that we don't know enough about.

Greater honeybee density had a positive effect on fly abundance, I caught these flies with pan traps.

So again, they probably spent more time flying around, we're more likely to encounter my traps and fall in.

So they may not actually be increasing abundance so much as increasing their likelihood of me who's collecting them.

To assess pollination, we took some weights, cemetery and seed set, which was really painstaking, there's not an easy way to count seed set but again, it's a direct one to one.

However, weight is actually incredibly correlated with seed set, I would probably just take weights and move on and the reason I took this data was because look at say, site 13.

I only had flies and very little of them.

Yet site 13 was kind of here in the middle of ballpark and they didn't really impact their yield tremendously.

But let's move over here and this site over here in orange is organic farms.

So you can see there's not a lot of difference between conventional organic.

All these pink purples represent flies.

The blue is native bees and the green is honey bees but you can see there's a lot of variability of pollinator communities but not a tremendous amount of variability in weight.

A lot of that kind of averages out in the end but site 16 that has a ton of pollinators really didn't have a huge increase in yield.

Now looking at 2018 data, same thing, site 13 had like nothing was living in the field.

They sprayed so often that I couldn't catch anything at all but their yield was perfectly fine.

So they don't need insects and some of that may have to do with the fact that they had a really large open field.

So there's probably a ton of wind borne pollen kind of moving around, a lot of airflow.

But ultimately, based on those other studies that have been done in the past, you would think that that cell fertilization would actually be detrimental.

But it could be that the varieties that we're growing now are very amenable to self fertilization.

A lot of the varieties we may be growing aren't quite the same as a lot of the historical data that we have on strawberries.

So neither native bee abundance or diversity was impacting weight or cemetery metrics.

So maybe we're reaching complete pollination with the native species that we have.

And that would include your bees and flies, obviously but when it comes to honey bees, we saw a really interesting trend.

As you the increase the amount of honey bees on your farm, you actually start to have a negative effect on your strawberry weight.

I can't necessarily say this is due to self fertilization.

Some people are suggesting that it's that lower quality pollen or maybe honey bees are removing enough free floating pollen to keep it from reaching other flowers.

But interestingly, if you have a larger field, so say more agricultural land and strawberries, you're gonna have a positive effect on berry symmetry, which again, makes sense because if you've got that open space, there's probably a lot more pollen moving around.

So what's different between our system and these other systems that can't even form a berry with self fertilization?

Probably has something to do with how amenable they are and I think a lot of work kind of needs to go into that, which is something we tried to do, so that's a common practice.

But that doesn't really work because that's neither natural or the microclimate you create in the bag itself can actually have an influence on berry production.

So every time we did this, you do get these really ugly berries from the ones in the bag and these really beautiful ones from the one on the open but it's not really representative of what's occurring on that plant.

So even if you had a single strawberry plant and wanted to look at self fertilization that plant will fertilize itself, not just one single flower to itself.

So we're like, cool, we'll cage the whole plant that was even worse, they really don't like that.

I had like all of the fruit (audience laughing)

that we tried to get just aborted.

It didn't develop anything.

We had a couple, but there was no point in measuring those, so we ate them.

But then we moved it into a greenhouse trial creating a bigger cage, one that allows for a little less of a difference in the climate.

So the temperature they love but again, trying to assess if you're open pollinated, and the plants that are not in cages will go outside just long enough for some insects to visit but we wanna know if they're allowed to have these insect visitors, this wind flow between plants, is that gonna be sufficient?

Or is a plant that's kind of just pollinating itself, is it still gonna be capable of producing berries?

Because that's really important if people bring 500 beehives to their farm, they may actually be making smaller berries and providing some sort of competition for their native species, especially if there's nothing else blooming and there's a finite amount of resources available for everybody to feed on.

Now, so then conclusion, obviously pesticides are having a negative impact on a lot of our bee populations but interestingly, some components of conventional management may be okay.

So that's something that we kind of need to drill down a little more.

What about our conventional farms was giving them some kind of an increase here?

The way in which you assess land cover is really gonna determine what kind of information you're gonna take from your data.

So while you would think that natural land is good, natural land doesn't mean ample food resources, diverse food resources, temporarily and spatially on a farm and also that increasing your density of managed honey bees could have variable effects on the pollinator community as a whole.

While it may decrease bee abundance maybe it increases fly, vice versa, there may be a lot of effects going on but it may also impact your yield.

And then really quick, as I mentioned before that pollinator complementarity, watch how that honey bee kind of walks across centrally on the flower kind of goes there.

They're mostly sitting on the top here and this is basically all they're doing and they're kind of moving around but ultimately staying in that same place.

Now this is a native bee and you'll see that once it actually gets positioned on the flower, it starts walking around the edges and it kind of gets down in there into the actual anthers itself, which is probably helping to knock pollen down.

So in the honey bee lands, a lot of the time is gonna be the pollen on the body that's gonna reach the center.

The native bee is likely knocking a lot of it down into the center and then the last thing I've got for you, this is a fly that looks tremendously like a bee in size and shape but you'll notice it actually has similar behavior where it likes to land on the central part of the flower and then just kind of hang out there and while they're not quite as hairy as a bee, if these plants happen to be amenable to self realization, that may be all it takes but if you're looking at how they actually forage on the flowers themselves, so you can see that having pollinator diversity can be really important because oftentimes there's gonna be a lot of variability in how they approach the flower and how they forage from it.

You see, it's looking for nectar there.