Photos contributed
The Bartier Brothers in their vineyard.
Michael Bartier, an Okanagan native, launched Bartier Brother Winery in 2015 on Ryegrass Road in Oliver with his older brother Donald, an accountant and oil and gas industry executive, as partner.
After graduating in recreational administration from the University of Victoria in 1990, Michael Bartier went into wine marketing. Not so keen about the selling part of the career, he returned to the Okanagan to become a “professional climbing guide” in 1995. Taking a job as cellar rat at Hawthorne Mountain Vineyards and being promoted to assistant winemaker by the end of the season was the beginning of his winemaking journey.
Since that time, Bartier has studied winemaking at American universities and worked at Township 7, Road 13 and Okanagan Crush Pad and making award-winning Chardonnays, before realizing his dream of opening his own Winery.
The fruit for Bartier Bros. 5,000 case a year winery is sourced from two estate vineyards. Between Black Sage Road and Okanagan River south of Oliver, the gently-sloping, west-facing 15 acre Cerqueira Vineyard consists of calcium carbonate-crusted rocks in the subsoil and top layers that Bartier describes as “glacial barf.” Planted between 1999 and 2009, it includes blocks of Merlot, Chardonnay, Cabernet Franc, Syrah and Semillon. Planted exclusively with Gewürtztraminer and situated on a steep ridge overlooking Okanagan Lake in Summerland, the two-acre Lone Pine Vineyard rests on the transition zone between ancient volcanic cone of Giant’s Head Mountain and silt from the glacial-formed banks of Lake Okanagan.
Winemaker Michael Bartier uses precision viticulture farming management practices. Precision viticulture (PV) recognizes that productivity within vineyards can vary widely and even blocks or zones within vineyards can vary significantly. In a nutshell, customizing suitable viticulture management practices to achieve production targets while minimizing environmental consequences encapsulates what PV is about. This is accomplished by collecting and interpreting a large amount of quantifiable data on specific blocks or zones that impact on grape yield and quality.
The size of the grape growing and winemaking operation is certainly a major factor in what and how much information is amassed and how it is used. But the methodology is accessible to smart, smaller producers who can utilize certain techniques selectively based on their specific needs. Winemaker Michael Bartier is one such producer who has adopted PV management practices as he strives to “make good wine and run a sustainable, profitable business, while enjoying an active, outdoor lifestyle.”
We asked Michael Bartier to tell us more about PV, and he answered with the help of Drew Campbell, an engineer with Terra Remote Sensing. Drew provides additional information on the technology and its applications. Campbell has flown several survey missions above the vineyard both with UAV (drones) and a helicopter.
How does PV assist you in growing grapes and making wine?
Michael Bartier: To make wine with special character, the key is to get the roots down and exploit the subsoil. To that end, I want to understand and classify substrates in our vineyards, an enormous challenge because of the homogeneously heterogeneous nature of the soils so prevalent in our vineyards and common in the Okanagan Valley.
I utilize underground and above ground PV data such as digging inspection pits, measuring electro-magnetic conductivity in soil and aerial photography for areas within a vineyard to determine the water retention capacities of the soils and provide patterns of vine vigour and disease susceptibility, which are not visible at ground level.
It allows me to adjust the factors – water, fertilizer, pruning and cover crop – to achieve objectively balanced vines that ripen as uniformly as possible and result in measurable improvement from year to year.
In the final analysis, PV is about the realities of business – growing more good grapes more efficiently while raising the value of the crop.
What is your definition of vineyard balance?
Michael Bartier: My personal definition of vineyard balance is a vineyard that grows enough canopy to ripen the fruit that it’s hanging, and no more canopy than that. If this happens, then the shoots stop growing on their own early in the summer without any topping or hedging done, and the vine focusses its energy into the fruit. If there’s not enough canopy, then the fruit won’t ripen and the vine is obviously weak. Too much canopy means the vegetative growth continues to the detriment of the fruit development and character, but also the shoots stay green as they grow, not getting themselves ready for the winter. Also, green shoots are susceptible to fungal diseases.
A vineyard in our region with a balanced canopy that starts to lignify in July is very healthy, needs little or no anti-fungal sprays, and produces world class fruit. Less expensive to farm, higher crop value, healthy vineyard with longer life-span - there’s no down side.
What are you looking for when digging inspection pits in the vineyard?
Michael Bartier: I’m most interested in rock types in the subsoils since I believe these impact the flavour of the wine eventually (controversial statement and NOT scientifically proven - just anecdotal observations made by most or all of the great winemakers in the world right now). Also the soil structure, and how the soil horizons (where the structure of a soil changes such as from topsoil to subsoil, and then there can be horizons below this, such as a silt hardpan, or a gravel seam, or sand, etc.) are ordered are very important. It’s difficult to coax the roots from the rich topsoil down into the all-important rocks if you can’t hold a bit of water in those subsoils; observing this helps to formulate a strategy. Bounce test is a very quick and easy field test for evaluating irrigation need, ridiculously simple, but effective and accurate; Take a palmful of soil from the soil at root depth below the vines of the block being evaluated. If you can compress this into a ball in your hand and bounce it in your palm a few times then no irrigation needed in my vineyard.
In the summer of 2016 we’ll be digging 200 cm inspection pits (calicata’s) and describing these by content, structure, and with typical soil analysis at each horizon (pH, CEC, salinity, etc).
How are the digs useful?
Michael Bartier: Soil compaction may be observed, showing us that the vine roots don’t have access to the important subsoils that we need them to get to for higher quality wine. Observing this structure can help us to strategize a way to break it up.
What types of images are used for gathering PV data and how are they used?
Michael Bartier: For me, most of the images are simply viewed on their own as pdf’s or photos. The images that I want to overlay are converted to kmz files (placemark file used for Google Earth) so that these can be imported directly to Google Earth which is the software platform I use to look at several layers of information on the same property at the same time or to be able to flip through them.
Drew Campbell: A wide range of images have been collected. These go from what would be considered industry standard, such as RGB, and wide band multispectral, to experimental, such as narrow band multispectral, hyperspectral, and LWIR (thermal), or long-range infrared. We also have point clouds derived from both photography and lidar.
These are processed into various products. Again, some standard, such as DVI, SAVI, and a DEM. The first two have been used to show vegetation health for years, the DEM shows high detail of bare earth contours which could be useful for predicting both water and air drainage. Cold air pooling? You guys will certainly be more familiar with the correct lingo here.
There are many more vegetation indices which can be produced. They are easily created through reasonably simple band math. This is the advantage in the collaboration between Terra and Michael Bartier. With his knowledge of his vineyard he can decide which are showing him something useful.
The software is a combination Terra developed for pre-processing and commercial software. I think here we’d prefer not to say which packages we’re using, it’s certainly nothing earth shattering, but we’ve spent hundreds of hours testing several software packages.
How do you collect the images?
Michael Bartier: Drones are capable of collecting all aerial images except LIDAR and Hyperspec. This is the most economical way of collecting data once it’s known exactly which we’re looking for. Helicopters are useful because of capacity and speed, able to collect huge amounts of all types of aerial images, but very expensive.
Drew Campbell: We used both platforms to give us data from many sensors. We are also working on a UAV solution which will produce the same array of products from our full helicopter platform. It will be a more robust model than we’re currently using, but hopefully can provide the best of both worlds. A multi-sensor platform, but still with the economy of a UAV.
Most of the cameras (excluding hyper and LWIR) are modified commercial cameras. The exact models we’d prefer not to divulge. However, they all run on fully custom software we’ve developed over many years.
Talon
The Talon helicopter used for recording the aerial images of Bartier Bros. vineyards in the Okanagan Valley.
What are multispectral, hyper, rpg, lidar images and how are they used to assess the status of your vines?
Michael Bartier: Each aerial photograph is taken with filters to see the reflected bandwidths (visible light and adjacent - near UV and near Infra Red) reflected from the surfaces of the vineyard. Some photos have very specific bandwidths or very broad, some show many ranges, some show just a few. Multispec shows a few very specific bandwidths that we know to show specific, telling information about what we’re looking at. Hyperspec shows many specific bandwidths which allows us to look at each, and compare this to known and observed conditions (e.g. disease presence, or water stress) in the vineyard, so that these can be quickly identified in the future just by going straight to those bandwidths. RGB images show the broad range of bandwidths making up the visible colours of Red, Green, and Blue. LIDAR is Light Radar measuring distance very accurately - essentially giving very accurate elevation maps of the terrain. CEM images (ElectroMagnetic Conductivity) are collected at ground level (for more information see this website) to read the soils ability to move electrons, correlating relatively well with the soils ability to hold water and thus predict vine vigour.
Drew Campbell: Sometimes it is with the aid of a filter and sometimes it is by removing a filter. Either way, both multispectral and hyperspectral collect many wavelengths which are invisible to humans. Some of these bands, for instance near infrared, are very useful in assessing vegetation… as said above. Others are being assessed to see which may show us something known to be true, which then could be used as a predictive tool.
We will also assess the value of vegetation indices produced with standard wide bands versus narrow band and even extremely narrow band. With the use of hyperspectral, we have the ability to get very narrow. As said, once it is discovered which works best, we can go straight to these in the future.
The lidar can be used to produce a DEM (elevation model), but also, when colourized with the photos, could provide a single product giving essentially everything we have discussed in one product. Point cloud, DEM, vegetation indices, etc, all in one product. Just turn layers on and off as desired for different views.
Please provide an example of benefit after physically checking area based on photo image data.
Michael Bartier: Comparing aerial photos with subsurface CEM images, and then visually observing the conditions in the vineyard foliage and canopy allows us to see the exact borders of an area that may be perfect balance, or may need different treatments - irrigation, fertilizer, disease control, etc.
Sometimes, just a regular RGB photo may be incredibly useful. The overhead plan view has many uses… general layout, irrigation planning, and a properly geo-referenced mosaic can be used for exact measurements.
